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2022 Volume 33 Issue 8
2022, 33(8): 3585-3593
doi: 10.1016/j.cclet.2021.09.029
Abstract:
Far-ranging and improper uses of pharmaceuticals and personal care products (PPCPs) over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system. Therefore, there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions. Adsorption technology is an appropriate technology to solve this issue. Carbon-based composites, ranging from modified activated carbon to functionalized biochar, show great potential for this purpose. This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents. The pore structure, relatively large specific surface area (SSA), abundant surface functional groups, highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance. Furthermore, the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs. Among the emerging adsorbents, graphene and carbon nanotubes composites show superior adsorption ability. Their adsorption mechanisms, such as electrostatic interactions, hydrogen bonding, and pore filling, are discussed in details.
Far-ranging and improper uses of pharmaceuticals and personal care products (PPCPs) over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system. Therefore, there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions. Adsorption technology is an appropriate technology to solve this issue. Carbon-based composites, ranging from modified activated carbon to functionalized biochar, show great potential for this purpose. This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents. The pore structure, relatively large specific surface area (SSA), abundant surface functional groups, highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance. Furthermore, the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs. Among the emerging adsorbents, graphene and carbon nanotubes composites show superior adsorption ability. Their adsorption mechanisms, such as electrostatic interactions, hydrogen bonding, and pore filling, are discussed in details.
2022, 33(8): 3594-3602
doi: 10.1016/j.cclet.2021.10.044
Abstract:
Hollow fiber microfiltration (MF) and ultrafiltration (UF) membrane processes have been extensively used in water purification and biotechnology. However, complicated filtration hydrodynamics wield a negative influence on fouling mitigation and stability of hollow fiber MF/UF membrane processes. Thus, establishing a mathematical model to understand the membrane processes is essential to guide the optimization of module configurations and to alleviate membrane fouling. Here, we present a comprehensive overview of the hollow fiber MF/UF membrane filtration models developed from different theories. The existing models primarily focus on membrane fouling but rarely on the interactions between the membrane fouling and local filtration hydrodynamics. Therefore, more simplified conceptual models and integrated reduced models need to be built to represent the real filtration behaviors of hollow fiber membranes. Future analyses considering practical requirements including complicated local hydrodynamics and nonuniform membrane properties are suggested to meet the accurate prediction of membrane filtration performance in practical application. This review will inspire the development of high-efficiency hollow fiber membrane modules.
Hollow fiber microfiltration (MF) and ultrafiltration (UF) membrane processes have been extensively used in water purification and biotechnology. However, complicated filtration hydrodynamics wield a negative influence on fouling mitigation and stability of hollow fiber MF/UF membrane processes. Thus, establishing a mathematical model to understand the membrane processes is essential to guide the optimization of module configurations and to alleviate membrane fouling. Here, we present a comprehensive overview of the hollow fiber MF/UF membrane filtration models developed from different theories. The existing models primarily focus on membrane fouling but rarely on the interactions between the membrane fouling and local filtration hydrodynamics. Therefore, more simplified conceptual models and integrated reduced models need to be built to represent the real filtration behaviors of hollow fiber membranes. Future analyses considering practical requirements including complicated local hydrodynamics and nonuniform membrane properties are suggested to meet the accurate prediction of membrane filtration performance in practical application. This review will inspire the development of high-efficiency hollow fiber membrane modules.
2022, 33(8): 3603-3612
doi: 10.1016/j.cclet.2021.10.053
Abstract:
Genomic deoxyribonucleic acid (DNA) is selected as the ideal carrier for preserving and transmitting the genetic information over the course of evolution. However, the genomic DNA is constantly exposed to various endogenous and environmental threats, causing a diversity of damaged bases, lesions, mismatches and base-pair modifications in the genome, eventually leading to genomic instability and cancers. Base excision repair (BER) is the most important repair mechanism, repairing a variety of DNA damages arising from oxidation, alkylation, methylation, deamination, and hydrolysis reactions. DNA glycosylases are responsible for initiating the first step of the BER pathway through cleaving the N-glycosidic bond between the damaged base and the DNA backbone. However, abnormal DNA glycosylases are associated with a variety of diseases such as cancer, cardiovascular disease, neurological disease and inflammation, suggesting the important role of DNA glycosylases in cancer diagnosis and treatment. Therefore, it is highly desirable to monitor the activity of DNA glycosylases, gaining a deep understanding of the restoration process of damaged DNA and clinical diagnosis. Recently, a series of novel DNA glycosylases detection methods with excellent performance have been developed. In this minireview, we summarize the recent advances in DNA glycosylase assays including amplification-free assay and amplification-assisted assay. Firstly, a brief introduction of amplification-free assay for DNA glycosylase is given. Then, amplification-assisted assays for DNA glycosylases are discussed in detail. Ultimately, the conclusion and prospects of the directions of DNA glycosylase assays are provided.
Genomic deoxyribonucleic acid (DNA) is selected as the ideal carrier for preserving and transmitting the genetic information over the course of evolution. However, the genomic DNA is constantly exposed to various endogenous and environmental threats, causing a diversity of damaged bases, lesions, mismatches and base-pair modifications in the genome, eventually leading to genomic instability and cancers. Base excision repair (BER) is the most important repair mechanism, repairing a variety of DNA damages arising from oxidation, alkylation, methylation, deamination, and hydrolysis reactions. DNA glycosylases are responsible for initiating the first step of the BER pathway through cleaving the N-glycosidic bond between the damaged base and the DNA backbone. However, abnormal DNA glycosylases are associated with a variety of diseases such as cancer, cardiovascular disease, neurological disease and inflammation, suggesting the important role of DNA glycosylases in cancer diagnosis and treatment. Therefore, it is highly desirable to monitor the activity of DNA glycosylases, gaining a deep understanding of the restoration process of damaged DNA and clinical diagnosis. Recently, a series of novel DNA glycosylases detection methods with excellent performance have been developed. In this minireview, we summarize the recent advances in DNA glycosylase assays including amplification-free assay and amplification-assisted assay. Firstly, a brief introduction of amplification-free assay for DNA glycosylase is given. Then, amplification-assisted assays for DNA glycosylases are discussed in detail. Ultimately, the conclusion and prospects of the directions of DNA glycosylase assays are provided.
2022, 33(8): 3613-3622
doi: 10.1016/j.cclet.2021.12.010
Abstract:
Chiral pillar[n]arenes have shown great research value and application prospect in construction of chiral materials and chiral applications, due to their inherent planar chiral configurations, chiral recognition ability, easy modification and highly symmetric hydrophobic cavity. This review systematically summarized the conformation inversion factors of planar chiral Pillar[5]arenes (pR/pS), such as solvents, temperature, substituent size, alkyl chains, chiral and achiral guest molecules. We firstly introduced the applications of chiral pillar[n]arenes for constructing chiral materials and pointed out that planar conformation inversion showed a great potential role in constructing chiral materials. Then, we mainly concluded the chiral applications of chiral and planar chiral pillar[n]arenes like chiral enantiomer analysis by circular dichroism, electrochemistry or chiral fluorescence sensing. From this review, we found that the inherent planar chiral conformation of chiral pillar[n]arenes have played a very important role in chiral field in the future.
Chiral pillar[n]arenes have shown great research value and application prospect in construction of chiral materials and chiral applications, due to their inherent planar chiral configurations, chiral recognition ability, easy modification and highly symmetric hydrophobic cavity. This review systematically summarized the conformation inversion factors of planar chiral Pillar[5]arenes (pR/pS), such as solvents, temperature, substituent size, alkyl chains, chiral and achiral guest molecules. We firstly introduced the applications of chiral pillar[n]arenes for constructing chiral materials and pointed out that planar conformation inversion showed a great potential role in constructing chiral materials. Then, we mainly concluded the chiral applications of chiral and planar chiral pillar[n]arenes like chiral enantiomer analysis by circular dichroism, electrochemistry or chiral fluorescence sensing. From this review, we found that the inherent planar chiral conformation of chiral pillar[n]arenes have played a very important role in chiral field in the future.
2022, 33(8): 3623-3631
doi: 10.1016/j.cclet.2021.11.041
Abstract:
As environmental crises such as global warming become more and more serious due to the large amount of carbon dioxide emitted by the burning of fossil fuels, much attention has been paid to carbon neutrality. Hydrogen, with zero carbon content, is a clean and renewable energy carrier having a large energy density. It is considered as one of the most desirable alternatives to fossil fuels. Electrochemical water splitting, unlike the steam reforming process accelerating fossil fuels depletion and CO2 emissions, can produce H2 powered by renewable energy such as solar or wind. As a promising way to promote carbon neutralization, hydrogen production by electrolysis of water is meaningful both in terms of scientific research and practical application. In order to drive electrochemical water splitting with low power consumption, efficient, durable and affordable electrocatalysts with low overpotentials are in urgent need. Therefore, this mini-review briefly introduces the current development status and mainstream obstacles of carbon-based materials used in electrochemical water splitting.
As environmental crises such as global warming become more and more serious due to the large amount of carbon dioxide emitted by the burning of fossil fuels, much attention has been paid to carbon neutrality. Hydrogen, with zero carbon content, is a clean and renewable energy carrier having a large energy density. It is considered as one of the most desirable alternatives to fossil fuels. Electrochemical water splitting, unlike the steam reforming process accelerating fossil fuels depletion and CO2 emissions, can produce H2 powered by renewable energy such as solar or wind. As a promising way to promote carbon neutralization, hydrogen production by electrolysis of water is meaningful both in terms of scientific research and practical application. In order to drive electrochemical water splitting with low power consumption, efficient, durable and affordable electrocatalysts with low overpotentials are in urgent need. Therefore, this mini-review briefly introduces the current development status and mainstream obstacles of carbon-based materials used in electrochemical water splitting.
2022, 33(8): 3632-3640
doi: 10.1016/j.cclet.2021.11.074
Abstract:
Photocatalytic optical fibers are promising for the degradation of gaseous and volatile pollutants in air due to their high specific surface area, high light utilization efficiency, easy regeneration, and sustainability. In particular, photocatalytic optical fibers have proven highly useful for the removal and conversion of different kinds of air pollutants in air. However, these fibers suffer from low photocatalytic degradation efficiencies. In this review, we have focused on introducing photocatalytic quartz optical fibers and photocatalytic plastic optical fibers for the degradation and transformation of gas-phase air pollutants. The principle of photocatalytic optical fibers and main methods for improving their photocatalytic and light utilization efficiencies based on semiconductor photocatalytic coatings are summarized. Moreover, the Langmuir-Hinshelwood kinetic rate equation was summarized to analyze the photocatalytic reduction of gaseous pollutants. Finally, an outlook on the future of photocatalytic optical fibers toward the removal and conversion of gaseous air pollutants is discussed.
Photocatalytic optical fibers are promising for the degradation of gaseous and volatile pollutants in air due to their high specific surface area, high light utilization efficiency, easy regeneration, and sustainability. In particular, photocatalytic optical fibers have proven highly useful for the removal and conversion of different kinds of air pollutants in air. However, these fibers suffer from low photocatalytic degradation efficiencies. In this review, we have focused on introducing photocatalytic quartz optical fibers and photocatalytic plastic optical fibers for the degradation and transformation of gas-phase air pollutants. The principle of photocatalytic optical fibers and main methods for improving their photocatalytic and light utilization efficiencies based on semiconductor photocatalytic coatings are summarized. Moreover, the Langmuir-Hinshelwood kinetic rate equation was summarized to analyze the photocatalytic reduction of gaseous pollutants. Finally, an outlook on the future of photocatalytic optical fibers toward the removal and conversion of gaseous air pollutants is discussed.
2022, 33(8): 3641-3649
doi: 10.1016/j.cclet.2021.12.018
Abstract:
Developing high-performance electrocatalysts for CO2 reduction reaction (CO2RR) is crucial since it is beneficial for environmental protection and the resulting value-add chemical products can act as an alternative to fossil feedstocks. Nonetheless, the direct reduction of CO2 into long-chain hydrocarbons and oxygenated hydrocarbons with high selectivity remains challenging. Copper (Cu) shows a distinctive advantage that it is the only pure metal catalyst for reducing CO2 into multi-carbon (C2+) products and the certain facets (e.g., (100), (111), (111)) of Cu nanocrystals exhibit relatively low energy barriers for the formation of specific products (e.g., CO, HCOOH, CH4, C2H4, C2H5OH, and other C2+ products). Therefore, extensive studies have been carried out to explore the relationship between the facets of Cu nanocrystals and corresponding catalytic products. In this review, we will discuss the crystal facet-dependent electrocatalytic CO2RR performance in metallic Cu catalysts, meanwhile, the detailed reaction mechanisms will be systematically summarized. In addition, we will provide a personal perspective for the future research directions in this emerging field. We believe this review is helpful to guide the design of high-selectivity Cu-based electrocatalysts for CO2RR.
Developing high-performance electrocatalysts for CO2 reduction reaction (CO2RR) is crucial since it is beneficial for environmental protection and the resulting value-add chemical products can act as an alternative to fossil feedstocks. Nonetheless, the direct reduction of CO2 into long-chain hydrocarbons and oxygenated hydrocarbons with high selectivity remains challenging. Copper (Cu) shows a distinctive advantage that it is the only pure metal catalyst for reducing CO2 into multi-carbon (C2+) products and the certain facets (e.g., (100), (111), (111)) of Cu nanocrystals exhibit relatively low energy barriers for the formation of specific products (e.g., CO, HCOOH, CH4, C2H4, C2H5OH, and other C2+ products). Therefore, extensive studies have been carried out to explore the relationship between the facets of Cu nanocrystals and corresponding catalytic products. In this review, we will discuss the crystal facet-dependent electrocatalytic CO2RR performance in metallic Cu catalysts, meanwhile, the detailed reaction mechanisms will be systematically summarized. In addition, we will provide a personal perspective for the future research directions in this emerging field. We believe this review is helpful to guide the design of high-selectivity Cu-based electrocatalysts for CO2RR.
2022, 33(8): 3650-3656
doi: 10.1016/j.cclet.2021.11.095
Abstract:
Manipulating the fluid transport in the microscale pores and channels is playing a paramount role in the realization of the versatile functions of microfluidics. In recent years, using light to control the fluid behavior in the microchannels/pores has attracted many researchers' attention due to the advantages of light such as non-contact stimulation, tunable excitation, high spatial and temporal resolution. With efforts, great achievements and progresses have been achieved for photochemical effect driven microscale flow control, including fluid pumping, flow rate control, and fluid mixing, etc. In this review, we discuss the responsive mechanisms of photochemical effect driven fluid behavior control at the microscale. We also give a comprehensive review on the latest research progresses in photochemical effect controlled microfluid behaviors. Besides, prospective opportunities for the future development of light control of microscale flow are provided to attract scientific interest for the fast development and applications of various microchannel/pore systems.
Manipulating the fluid transport in the microscale pores and channels is playing a paramount role in the realization of the versatile functions of microfluidics. In recent years, using light to control the fluid behavior in the microchannels/pores has attracted many researchers' attention due to the advantages of light such as non-contact stimulation, tunable excitation, high spatial and temporal resolution. With efforts, great achievements and progresses have been achieved for photochemical effect driven microscale flow control, including fluid pumping, flow rate control, and fluid mixing, etc. In this review, we discuss the responsive mechanisms of photochemical effect driven fluid behavior control at the microscale. We also give a comprehensive review on the latest research progresses in photochemical effect controlled microfluid behaviors. Besides, prospective opportunities for the future development of light control of microscale flow are provided to attract scientific interest for the fast development and applications of various microchannel/pore systems.
2022, 33(8): 3657-3671
doi: 10.1016/j.cclet.2021.12.001
Abstract:
Electrocatalytic oxygen evolution reaction (OER) is one of the important half reactions of electrocatalytic water splitting. However, the slow kinetic process involving four-electron transfer severely limits its reaction efficiency, which in turn limits the overall electrocatalytic hydrolysis efficiency. In order to improve the activity of the electrocatalytic OER, researchers mainly update the catalyst from three aspects, that is, increase the conductivity of the electrocatalyst, and the quantity and quality of active sites. Two-dimensional (2D) engineering can effectively reduce the resistance of the materials and greatly increase the number of electrochemically active sites, while heterometal doping, or the bimetal strategy, can improve the quality of active sites via changing the electronic structure of the material. Thus, the combination of the two can enhance the activity of electrocatalytic OER in all three aspects: conductivity, number and quality of active sites. However, there is currently no review on this topic. Therefore, in this review, we summarize the application of bimetallic 2D materials in electrocatalytic OER from four aspects: the structure, synthesis strategy, catalytic efficiency, and reaction mechanism.
Electrocatalytic oxygen evolution reaction (OER) is one of the important half reactions of electrocatalytic water splitting. However, the slow kinetic process involving four-electron transfer severely limits its reaction efficiency, which in turn limits the overall electrocatalytic hydrolysis efficiency. In order to improve the activity of the electrocatalytic OER, researchers mainly update the catalyst from three aspects, that is, increase the conductivity of the electrocatalyst, and the quantity and quality of active sites. Two-dimensional (2D) engineering can effectively reduce the resistance of the materials and greatly increase the number of electrochemically active sites, while heterometal doping, or the bimetal strategy, can improve the quality of active sites via changing the electronic structure of the material. Thus, the combination of the two can enhance the activity of electrocatalytic OER in all three aspects: conductivity, number and quality of active sites. However, there is currently no review on this topic. Therefore, in this review, we summarize the application of bimetallic 2D materials in electrocatalytic OER from four aspects: the structure, synthesis strategy, catalytic efficiency, and reaction mechanism.
2022, 33(8): 3672-3680
doi: 10.1016/j.cclet.2021.12.016
Abstract:
Carboranes are a class of polyhedral boron-carbon molecular clusters, they can serve as versatile ligands in stabilizing low-valent main group element compounds, due to their exceptionally thermal and chemical stabilities, easy modifications at the cage carbon vertices, as well as large spherical steric effects. These carborane-based ligands provide interesting opportunities for the synthesis of low-valent main group element compounds with novel structure and reactivity, which indeed enrich the chemistry of low-valent element main group compounds. This review summarizes the recent advances in the chemistry of low-valent group 13 and group 14 element compounds supported by carborane-based ligands. Achievements and perspectives in this new and flourishing field are discussed in this review.
Carboranes are a class of polyhedral boron-carbon molecular clusters, they can serve as versatile ligands in stabilizing low-valent main group element compounds, due to their exceptionally thermal and chemical stabilities, easy modifications at the cage carbon vertices, as well as large spherical steric effects. These carborane-based ligands provide interesting opportunities for the synthesis of low-valent main group element compounds with novel structure and reactivity, which indeed enrich the chemistry of low-valent element main group compounds. This review summarizes the recent advances in the chemistry of low-valent group 13 and group 14 element compounds supported by carborane-based ligands. Achievements and perspectives in this new and flourishing field are discussed in this review.
2022, 33(8): 3681-3694
doi: 10.1016/j.cclet.2021.11.018
Abstract:
Three-dimensional (3D) printing, also known as additive manufacturing, has the advantages of low cost, easy structure operation, rapid prototyping, and easy customization. In the past few years, materials with different structures, compositions, and properties have been widely studied as prospects in the field of 3D printing. This paper reviews the synthesis methods and morphologies of one-, two- and three-dimensional micro/nano materials and their composites, as well as their applications in electrochemistry, such as supercapacitors, batteries and electrocatalysis. The latest progress and breakthroughs in the synthesis and application of different structural materials in 3D-printing materials, as well as the challenges and prospects of electrochemical applications, are discussed.
Three-dimensional (3D) printing, also known as additive manufacturing, has the advantages of low cost, easy structure operation, rapid prototyping, and easy customization. In the past few years, materials with different structures, compositions, and properties have been widely studied as prospects in the field of 3D printing. This paper reviews the synthesis methods and morphologies of one-, two- and three-dimensional micro/nano materials and their composites, as well as their applications in electrochemistry, such as supercapacitors, batteries and electrocatalysis. The latest progress and breakthroughs in the synthesis and application of different structural materials in 3D-printing materials, as well as the challenges and prospects of electrochemical applications, are discussed.
2022, 33(8): 3695-3700
doi: 10.1016/j.cclet.2022.03.073
Abstract:
Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge. Diazenes, including 1, 1-diazenes and 1, 2-diazenes, can generate biradical species via nitrogen extrusion under thermal or photochemical conditions. The superior reactivity of the generated biradical enables various types of synthetic transformations with excellent chemoselectivity and has been applied to the complex natural products synthesis. In this mini-review, the modes of reaction are summarized and discussed, namely ring contraction via nitrogen deletion, homo or heterodimerization, trimethylenemethane (TMM)-diyl cycloaddition. Applications of these classes of reactions in complex natural product synthesis are illustrated. Last but not least, the current state, future directions, and opportunities for dinitrogen extrusion reaction from diazenes are highlighted and discussed.
Radical-mediated reactions have many advantages in the construction of complex molecular scaffolds by forging chemical bonds of high challenge. Diazenes, including 1, 1-diazenes and 1, 2-diazenes, can generate biradical species via nitrogen extrusion under thermal or photochemical conditions. The superior reactivity of the generated biradical enables various types of synthetic transformations with excellent chemoselectivity and has been applied to the complex natural products synthesis. In this mini-review, the modes of reaction are summarized and discussed, namely ring contraction via nitrogen deletion, homo or heterodimerization, trimethylenemethane (TMM)-diyl cycloaddition. Applications of these classes of reactions in complex natural product synthesis are illustrated. Last but not least, the current state, future directions, and opportunities for dinitrogen extrusion reaction from diazenes are highlighted and discussed.
2022, 33(8): 3701-3704
doi: 10.1016/j.cclet.2021.10.065
Abstract:
Electrochemical degradation performances of three non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen (ACT), aspirin (ASP) and ibuprofen (IBP), were investigated and compared in their alone and mixture conditions using Ti/SnO2-Sb/La-PbO2. The pseudo-first-order degradation kinetics (k) order was kIBP-A (0.110 min−1) > kASP-A (0.092 min−1) > kACT-A (0.066 min−1) in their alone condition, while that was kACT-M (0.088 min−1) > kASP-M (0.063 min−1) > kIBP-M (0.057 min−1) in their mixture condition. The •OH apparent production rate constant of 5.23 mmol L−1 min−1 m−2 and an electrical energy per order (EEO) value of 6.55 Wh/L could ensure the synchronous degradation of the NSAIDs mixture. The mineralization efficiency of NSAIDs mixture was 86.9% at 240 min with a mineralization current efficiency of 1.67%. Acetic acid and oxalic acid were the main products in the mineralization process for the both conditions. In the mixture condition, there were higher k values at lower initial concentrations and higher current density, while the presence of carbonate and humic acid inhibited their degradation. The results indicated electrochemical advanced oxidation process can effectively and synchronously mineralize NSAIDs mixture in wastewater.
Electrochemical degradation performances of three non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen (ACT), aspirin (ASP) and ibuprofen (IBP), were investigated and compared in their alone and mixture conditions using Ti/SnO2-Sb/La-PbO2. The pseudo-first-order degradation kinetics (k) order was kIBP-A (0.110 min−1) > kASP-A (0.092 min−1) > kACT-A (0.066 min−1) in their alone condition, while that was kACT-M (0.088 min−1) > kASP-M (0.063 min−1) > kIBP-M (0.057 min−1) in their mixture condition. The •OH apparent production rate constant of 5.23 mmol L−1 min−1 m−2 and an electrical energy per order (EEO) value of 6.55 Wh/L could ensure the synchronous degradation of the NSAIDs mixture. The mineralization efficiency of NSAIDs mixture was 86.9% at 240 min with a mineralization current efficiency of 1.67%. Acetic acid and oxalic acid were the main products in the mineralization process for the both conditions. In the mixture condition, there were higher k values at lower initial concentrations and higher current density, while the presence of carbonate and humic acid inhibited their degradation. The results indicated electrochemical advanced oxidation process can effectively and synchronously mineralize NSAIDs mixture in wastewater.
2022, 33(8): 3705-3708
doi: 10.1016/j.cclet.2021.10.080
Abstract:
A kind of CdS/Cd-BiOCl immobilized films photocatalyst was prepared. The optical and physicochemical properties of the CdS/Cd-BiOCl photocatalysts were analysed, and the detailed characterization revealed CdS/Cd-BiOCl films photocatalyst with good charge carrier separation effect. The reusabilities and photocatalytic properties of the samples were studied. The 15%CdS/Cd-BiOCl photocatalyst exhibited superior performance in photocatalytic degradation of tetracycline (TC) and favorable stability under visible light irradiation. As for the photodegradation rate of TC, 15%CdS/Cd-BiOCl exhibited an excellent photodegradation activity, which is 4.06 and 9.53 times higher than that of CdS/Cd and BiOCl, respectively. The results showed that dominant active species are •O2− and •OH radicals during photodegradation. The charge transfer in Z-scheme CdS/Cd-BiOCl films photocatalyst could synchronously generate conduct band (CB) electrons in BiOCl and valence band (VB) holes in CdS, and metal Cd served as electron mediator. This work can be a reference for the design of film photocatalysts and new insight for photodegradating towards contaminants.
A kind of CdS/Cd-BiOCl immobilized films photocatalyst was prepared. The optical and physicochemical properties of the CdS/Cd-BiOCl photocatalysts were analysed, and the detailed characterization revealed CdS/Cd-BiOCl films photocatalyst with good charge carrier separation effect. The reusabilities and photocatalytic properties of the samples were studied. The 15%CdS/Cd-BiOCl photocatalyst exhibited superior performance in photocatalytic degradation of tetracycline (TC) and favorable stability under visible light irradiation. As for the photodegradation rate of TC, 15%CdS/Cd-BiOCl exhibited an excellent photodegradation activity, which is 4.06 and 9.53 times higher than that of CdS/Cd and BiOCl, respectively. The results showed that dominant active species are •O2− and •OH radicals during photodegradation. The charge transfer in Z-scheme CdS/Cd-BiOCl films photocatalyst could synchronously generate conduct band (CB) electrons in BiOCl and valence band (VB) holes in CdS, and metal Cd served as electron mediator. This work can be a reference for the design of film photocatalysts and new insight for photodegradating towards contaminants.
2022, 33(8): 3709-3712
doi: 10.1016/j.cclet.2021.10.047
Abstract:
Semiconductor-employed photocatalytic CO2 reduction has been regarded as a promising approach for environmental-friendly conversion of CO2 into solar fuels. Herein, TiO2/Cu2O composite nanorods have been successfully fabricated by a facile chemical reduction method and applied for photocatalytic CO2 reduction. The composition and structure characterization indicates that the Cu2O nanoparticles are coupled with TiO2 nanorods with an intimate contact. Under light illumination, all the TiO2/Cu2O composite nanorods enhance the photocatalytic CO2 reduction. In particular, the TiO2/Cu2O-15% sample exhibits the highest CH4 yield (1.35 µmol g-1 h-1) within 4 h irradiation, and it is 3.07 and 15 times higher than that of pristine TiO2 nanorods and Cu2O nanoparticles, respectively. The enhanced photoreduction capability of the TiO2/Cu2O-15% is attributed to the intimate construction of Cu2O nanoparticles on TiO2 nanorods with formed p-n junction to accelerate the separation of photogenerated electron-hole pairs. This work provides a reference for rational design of a p-n heterojunction photocatalyst for CO2 photoreduction.
Semiconductor-employed photocatalytic CO2 reduction has been regarded as a promising approach for environmental-friendly conversion of CO2 into solar fuels. Herein, TiO2/Cu2O composite nanorods have been successfully fabricated by a facile chemical reduction method and applied for photocatalytic CO2 reduction. The composition and structure characterization indicates that the Cu2O nanoparticles are coupled with TiO2 nanorods with an intimate contact. Under light illumination, all the TiO2/Cu2O composite nanorods enhance the photocatalytic CO2 reduction. In particular, the TiO2/Cu2O-15% sample exhibits the highest CH4 yield (1.35 µmol g-1 h-1) within 4 h irradiation, and it is 3.07 and 15 times higher than that of pristine TiO2 nanorods and Cu2O nanoparticles, respectively. The enhanced photoreduction capability of the TiO2/Cu2O-15% is attributed to the intimate construction of Cu2O nanoparticles on TiO2 nanorods with formed p-n junction to accelerate the separation of photogenerated electron-hole pairs. This work provides a reference for rational design of a p-n heterojunction photocatalyst for CO2 photoreduction.
2022, 33(8): 3713-3720
doi: 10.1016/j.cclet.2021.11.096
Abstract:
Eggshell-loaded CoFe2O4 catalyst was synthesized via a convenient hydrothermal method during our work, then the surface morphology and elemental composition of the composites were systematically investigated. Performance of CoFe2O4/eggshell-activated peroxymonosulfate (PMS) system was evaluated by selecting florfenicol (FF) as the model pollutant, and effects of operating parameters and water matrices on the FF removal efficiency in this system were investigated. In addition, main radicals involved in FF degradation were identified by EPR tests and radical quenching experiments, and possible mechanism was proposed. The reduction of toxicity during FF degradation was confirmed, and in combination with HP-LC tests, it was found that dehalogenation and defluorination were effectively carried out during FF degradation. In addition, the prepared CoFe2O4 polyvinylidene fluoride (PVDF) membrane effectively improved the stability of the material and reduced the precipitation of metals.
Eggshell-loaded CoFe2O4 catalyst was synthesized via a convenient hydrothermal method during our work, then the surface morphology and elemental composition of the composites were systematically investigated. Performance of CoFe2O4/eggshell-activated peroxymonosulfate (PMS) system was evaluated by selecting florfenicol (FF) as the model pollutant, and effects of operating parameters and water matrices on the FF removal efficiency in this system were investigated. In addition, main radicals involved in FF degradation were identified by EPR tests and radical quenching experiments, and possible mechanism was proposed. The reduction of toxicity during FF degradation was confirmed, and in combination with HP-LC tests, it was found that dehalogenation and defluorination were effectively carried out during FF degradation. In addition, the prepared CoFe2O4 polyvinylidene fluoride (PVDF) membrane effectively improved the stability of the material and reduced the precipitation of metals.
2022, 33(8): 3721-3725
doi: 10.1016/j.cclet.2021.10.063
Abstract:
Self-supported transition-metal single-atom catalysts (SACs) facilitate the industrialization of electrochemical CO2 reduction, but suffer from high structural heterogeneity with limited catalytic selectivity. Here we present a facile and scalable approach for the synthesis of self-supported nickel@nitrogen-doped carbon nanotubes grown on carbon nanofiber membrane (Ni@NCNTs/CFM), where the Ni single atoms and nanoparticles (NPs) are anchored on the wall and inside of nitrogen-doped carbon nanotubes, respectively. The side effect of Ni NPs was further effectively inhibited by alloying Ni with Cu atoms to alter their d-band center, which is theoretically predicted and experimentally proved. The optimal catalyst Ni9Cu1@NCNTs/CFM exhibits an ultrahigh CO Faradic efficiency over 97% at −0.7 V versus reversible hydrogen electrode. Additionally, this catalyst shows excellent mechanical strength which can be directly used as a self-supporting catalyst for Zn-CO2 battery with a peak power density of ~0.65 mW/cm2 at 2.25 mA/cm2 and a long-term stability for 150 cycles. This work opens up a general avenue to facilely prepare self-supported SACs with unitary single-atom site for CO2 utilization.
Self-supported transition-metal single-atom catalysts (SACs) facilitate the industrialization of electrochemical CO2 reduction, but suffer from high structural heterogeneity with limited catalytic selectivity. Here we present a facile and scalable approach for the synthesis of self-supported nickel@nitrogen-doped carbon nanotubes grown on carbon nanofiber membrane (Ni@NCNTs/CFM), where the Ni single atoms and nanoparticles (NPs) are anchored on the wall and inside of nitrogen-doped carbon nanotubes, respectively. The side effect of Ni NPs was further effectively inhibited by alloying Ni with Cu atoms to alter their d-band center, which is theoretically predicted and experimentally proved. The optimal catalyst Ni9Cu1@NCNTs/CFM exhibits an ultrahigh CO Faradic efficiency over 97% at −0.7 V versus reversible hydrogen electrode. Additionally, this catalyst shows excellent mechanical strength which can be directly used as a self-supporting catalyst for Zn-CO2 battery with a peak power density of ~0.65 mW/cm2 at 2.25 mA/cm2 and a long-term stability for 150 cycles. This work opens up a general avenue to facilely prepare self-supported SACs with unitary single-atom site for CO2 utilization.
2022, 33(8): 3726-3732
doi: 10.1016/j.cclet.2021.11.002
Abstract:
As a common volatile organic compound, benzene (C6H6) exists in home decoration pollution gas widely, which causes great harm to the environment and human health. Therefore, it is necessary to rationally design advanced materials with high selectivity to detect and capture C6H6. Herein, combined with the d-band center theory and cohesive energy, a new two-dimensional metal-organic framework material, Ni-doped hexaaminobenzene-based coordination polymer (Ni-HAB-CP) is designed, and its application potential as a C6H6 sensor are systematically investigated by using first principles calculation. The result shows that Ni-HAB-CP has a strong adsorption for C6H6 without any additional method. In addition, Ni-HAB-CP can maintain good conductivity before and after adsorption, and C6H6 can be easily desorbed from the surface of Ni-HAB-CP by charge control. Moreover, the I-V curve calculated by Atomistix Toolkit (ATK) reveals that Ni-HAB-CP has high sensitivity and selectivity to C6H6. Hence, Ni-HAB-CP is expected to be used as a potential material for a highly efficient and recyclable C6H6 sensor in the future. The calculation and analysis methods used in this paper could provide a certain theoretical basis and reference for the future research of gas sensors.
As a common volatile organic compound, benzene (C6H6) exists in home decoration pollution gas widely, which causes great harm to the environment and human health. Therefore, it is necessary to rationally design advanced materials with high selectivity to detect and capture C6H6. Herein, combined with the d-band center theory and cohesive energy, a new two-dimensional metal-organic framework material, Ni-doped hexaaminobenzene-based coordination polymer (Ni-HAB-CP) is designed, and its application potential as a C6H6 sensor are systematically investigated by using first principles calculation. The result shows that Ni-HAB-CP has a strong adsorption for C6H6 without any additional method. In addition, Ni-HAB-CP can maintain good conductivity before and after adsorption, and C6H6 can be easily desorbed from the surface of Ni-HAB-CP by charge control. Moreover, the I-V curve calculated by Atomistix Toolkit (ATK) reveals that Ni-HAB-CP has high sensitivity and selectivity to C6H6. Hence, Ni-HAB-CP is expected to be used as a potential material for a highly efficient and recyclable C6H6 sensor in the future. The calculation and analysis methods used in this paper could provide a certain theoretical basis and reference for the future research of gas sensors.
2022, 33(8): 3733-3738
doi: 10.1016/j.cclet.2021.10.068
Abstract:
Designing visible light photocatalysts with a metal oxide semiconductor as the starting material could expand a new horizon for the conversion and storage of solar energy. Here, the benchmark photocatalyst TiO2 was used to pursue this goal by anchoring aromatic acids. Extending the aromatic acid was strategically deployed to design TiO2 complexes with violet light-induced selective aerobic oxidation of sulfide as the probe reaction. With benzoic acid (BA) as the initial molecule, horizontally extending one or two benzene rings furnishes 2-naphthoic acid (2-NA) and 2-anthracene acid (2-AA). Moreover, triethylamine (TEA), an electron transfer mediator, was introduced to maintain the integrity of the anchored aromatic acids. Notably, there was a direct correlation between the π-conjugation of aromatic acid ligand and the selective aerobic oxidation of sulfides. Among the three aromatic acids, 2-AA delivered the best result over TiO2 due to the most extensive π-conjugated system. Ultimately, violet light-induced selective aerobic oxidation of sulfides into corresponding sulfoxides was conveniently realized by cooperative photocatalysis of 2-AA-TiO2 with 10 mol% of TEA. This work affords an extending strategy for designing the next-generation ligands for semiconductors to expand visible light-induced selective reactions.
Designing visible light photocatalysts with a metal oxide semiconductor as the starting material could expand a new horizon for the conversion and storage of solar energy. Here, the benchmark photocatalyst TiO2 was used to pursue this goal by anchoring aromatic acids. Extending the aromatic acid was strategically deployed to design TiO2 complexes with violet light-induced selective aerobic oxidation of sulfide as the probe reaction. With benzoic acid (BA) as the initial molecule, horizontally extending one or two benzene rings furnishes 2-naphthoic acid (2-NA) and 2-anthracene acid (2-AA). Moreover, triethylamine (TEA), an electron transfer mediator, was introduced to maintain the integrity of the anchored aromatic acids. Notably, there was a direct correlation between the π-conjugation of aromatic acid ligand and the selective aerobic oxidation of sulfides. Among the three aromatic acids, 2-AA delivered the best result over TiO2 due to the most extensive π-conjugated system. Ultimately, violet light-induced selective aerobic oxidation of sulfides into corresponding sulfoxides was conveniently realized by cooperative photocatalysis of 2-AA-TiO2 with 10 mol% of TEA. This work affords an extending strategy for designing the next-generation ligands for semiconductors to expand visible light-induced selective reactions.
2022, 33(8): 3739-3744
doi: 10.1016/j.cclet.2021.10.088
Abstract:
Elemental doping confined in atomically-thin 2D semiconductors offers a compelling strategy for constructing high performance photocatalysts. Although impressive progress has been achieved based on co-thermolysis method, the choices of dopants as well as semiconductor hosts are still quite limited to yield the elaborate photocatalyst with atomic-layer-confined doping defects, owing to the difficulty in balancing the reaction kinetics of different precursors. This study shows that the cation exchange reaction, which is dictated by the Pearson's hard and soft acids and bases (HSAB) theory and allowed to proceed at mild temperatures, can be developed into a conceptually new protocol for engineering elemental doping confined in semiconductor atomic layers. To this aim, the two atomic layers of a new type of 2D photocatalyst PdSeO3 (PdSeO3 2ALs, 1.1 nm) are created by liquid exfoliation and exploited as a proof-of-concept prototype. It is demonstrated that the Mn(II) dopants with controlled concentrations can be incorporated into PdSeO3 2ALs via topological Mn2+-for-Pd2+ cation exchange performed in water/isopropanol solution at 30 ℃. The resulting Mn-doped PdSeO3 2ALs present enhanced capacity for driving photocatalytic oxidation reactions in comparison with their undoped counterparts. The findings here suggest that the new route mediated by post synthetic cation exchange promises to give access to manifold 2D confined-doping photocatalysts, with little perturbations on the thickness, morphology, and crystal structure of the atomically-thin semiconductor hosts.
Elemental doping confined in atomically-thin 2D semiconductors offers a compelling strategy for constructing high performance photocatalysts. Although impressive progress has been achieved based on co-thermolysis method, the choices of dopants as well as semiconductor hosts are still quite limited to yield the elaborate photocatalyst with atomic-layer-confined doping defects, owing to the difficulty in balancing the reaction kinetics of different precursors. This study shows that the cation exchange reaction, which is dictated by the Pearson's hard and soft acids and bases (HSAB) theory and allowed to proceed at mild temperatures, can be developed into a conceptually new protocol for engineering elemental doping confined in semiconductor atomic layers. To this aim, the two atomic layers of a new type of 2D photocatalyst PdSeO3 (PdSeO3 2ALs, 1.1 nm) are created by liquid exfoliation and exploited as a proof-of-concept prototype. It is demonstrated that the Mn(II) dopants with controlled concentrations can be incorporated into PdSeO3 2ALs via topological Mn2+-for-Pd2+ cation exchange performed in water/isopropanol solution at 30 ℃. The resulting Mn-doped PdSeO3 2ALs present enhanced capacity for driving photocatalytic oxidation reactions in comparison with their undoped counterparts. The findings here suggest that the new route mediated by post synthetic cation exchange promises to give access to manifold 2D confined-doping photocatalysts, with little perturbations on the thickness, morphology, and crystal structure of the atomically-thin semiconductor hosts.
2022, 33(8): 3745-3751
doi: 10.1016/j.cclet.2021.11.007
Abstract:
Hydrogen evolution reaction (HER) catalytic electrodes under actual working conditions show interesting mass transfer behaviors at solid (electrode)/liquid (electrolyte)/gas (hydrogen) three-phase interfaces. These behaviors are essential for forming a continuous and effective physical contact region between the electrolyte and the electrode and require further detailed understanding. Here, a case study on 1T-2H phase molybdenum disulfide (MoS2)/carbon fiber paper (CFP) catalytic electrodes is performed. Rapid gas-liquid mass transfer at the interface for enhancing the working area stability and capillarity for increasing the electrode working area is found. The real scenario, wherein the energy utilization efficiency of the as-prepared non-noble metal catalytic electrode exceeds that of the noble metal catalytic electrode, is disclosed. Specifically, a fluid dynamics model is developed to investigate the behavior mechanism of hydrogen bubbles from generation to desorption on the catalytic electrode surface with different hydrophilic and hydrophobic properties. These new insights and theoretical evidence on the non-negligible three-phase interface behaviors will identify opportunities and motivate future research in high-efficiency, stability, and low-cost HER catalytic electrode development.
Hydrogen evolution reaction (HER) catalytic electrodes under actual working conditions show interesting mass transfer behaviors at solid (electrode)/liquid (electrolyte)/gas (hydrogen) three-phase interfaces. These behaviors are essential for forming a continuous and effective physical contact region between the electrolyte and the electrode and require further detailed understanding. Here, a case study on 1T-2H phase molybdenum disulfide (MoS2)/carbon fiber paper (CFP) catalytic electrodes is performed. Rapid gas-liquid mass transfer at the interface for enhancing the working area stability and capillarity for increasing the electrode working area is found. The real scenario, wherein the energy utilization efficiency of the as-prepared non-noble metal catalytic electrode exceeds that of the noble metal catalytic electrode, is disclosed. Specifically, a fluid dynamics model is developed to investigate the behavior mechanism of hydrogen bubbles from generation to desorption on the catalytic electrode surface with different hydrophilic and hydrophobic properties. These new insights and theoretical evidence on the non-negligible three-phase interface behaviors will identify opportunities and motivate future research in high-efficiency, stability, and low-cost HER catalytic electrode development.
2022, 33(8): 3752-3756
doi: 10.1016/j.cclet.2021.11.063
Abstract:
Hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) have been considered as two critical processes in the field of electrocatalytic water-splitting for hydrogen production and fuel cells. However, the sluggish reaction kinetics of HER and ORR required efficient electrocatalyst such as Pt to promote such process. Transition metal phosphides (TMPs) exhibit great potential to replace noble metal electrocatalysts to accelerate HER and ORR due to their high activity and easy availability. Herein, a highly-efficient bifunctional CoP electrocatalyst for HER and ORR, featuring a unique core-shell structure decorated on nitrogen-doped carbon matrix was designed and constructed via etching a cobalt-based zeolitic imidazolate framework (ZIF-67) with phytic acid (PA) followed by pyrolysis treatment (PA-ZIF-67–900). Experimental results revealed that the pure-phase single-crystalline CoP exhibited outstanding electrocatalytic performance in HER and ORR, superior to Co(PO3)2 in PA-ZIF-67–700, hybrid phase of Co(PO3)2 and CoP in PA-ZIF-67–800 and Co2P-doped CoP in PA-ZIF-67–1000. To reach the current density of 10 mA/cm2 the as-synthesized CoP required an overpotential of 120 mV for HER in 1 mol/L KOH and half-wave potential of 0.85 V in O2-saturated 0.1 mol/L KOH. This work present new clue for construction of efficient and bifunctional electrocatalyst in the field of energy conversion and storage
Hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) have been considered as two critical processes in the field of electrocatalytic water-splitting for hydrogen production and fuel cells. However, the sluggish reaction kinetics of HER and ORR required efficient electrocatalyst such as Pt to promote such process. Transition metal phosphides (TMPs) exhibit great potential to replace noble metal electrocatalysts to accelerate HER and ORR due to their high activity and easy availability. Herein, a highly-efficient bifunctional CoP electrocatalyst for HER and ORR, featuring a unique core-shell structure decorated on nitrogen-doped carbon matrix was designed and constructed via etching a cobalt-based zeolitic imidazolate framework (ZIF-67) with phytic acid (PA) followed by pyrolysis treatment (PA-ZIF-67–900). Experimental results revealed that the pure-phase single-crystalline CoP exhibited outstanding electrocatalytic performance in HER and ORR, superior to Co(PO3)2 in PA-ZIF-67–700, hybrid phase of Co(PO3)2 and CoP in PA-ZIF-67–800 and Co2P-doped CoP in PA-ZIF-67–1000. To reach the current density of 10 mA/cm2 the as-synthesized CoP required an overpotential of 120 mV for HER in 1 mol/L KOH and half-wave potential of 0.85 V in O2-saturated 0.1 mol/L KOH. This work present new clue for construction of efficient and bifunctional electrocatalyst in the field of energy conversion and storage
2022, 33(8): 3757-3761
doi: 10.1016/j.cclet.2021.11.077
Abstract:
Selective hydrogenation of cinnamaldehyde (CAL) toward cinnamyl alcohol (COL) is an extremely important and challenging reaction. Herein, a series of PtxFey-Al2O3 bimetallic catalysts with varied Pt to Fe ratios were prepared by incipient wetness impregnation method. The introduction of Fe significantly modifies the electronic and surface properties of Pt, which clearly enhances the C=O hydrogenation selectivity. Among all the catalysts, Pt3Fe-Al2O3 displays the best catalytic performance and the conversion of CAL is 96.6% with 77.2% selectivity of COL within 1 h. In addition, Pt3Fe-Al2O3 had excellent reusability with 76% COL selectivity after five runs of the recycle process. Further characterization of the fresh, used and cycled catalysts revealed that the structure and electronic state of the synthesized PtxFey-Al2O3 are unchanged after hydrogenation reaction. The identical-location transmission electron microscopy (IL-TEM) results revealed that the interaction between the nanoparticles and the supports was strong and the catalyst was relatively stable.
Selective hydrogenation of cinnamaldehyde (CAL) toward cinnamyl alcohol (COL) is an extremely important and challenging reaction. Herein, a series of PtxFey-Al2O3 bimetallic catalysts with varied Pt to Fe ratios were prepared by incipient wetness impregnation method. The introduction of Fe significantly modifies the electronic and surface properties of Pt, which clearly enhances the C=O hydrogenation selectivity. Among all the catalysts, Pt3Fe-Al2O3 displays the best catalytic performance and the conversion of CAL is 96.6% with 77.2% selectivity of COL within 1 h. In addition, Pt3Fe-Al2O3 had excellent reusability with 76% COL selectivity after five runs of the recycle process. Further characterization of the fresh, used and cycled catalysts revealed that the structure and electronic state of the synthesized PtxFey-Al2O3 are unchanged after hydrogenation reaction. The identical-location transmission electron microscopy (IL-TEM) results revealed that the interaction between the nanoparticles and the supports was strong and the catalyst was relatively stable.
2022, 33(8): 3762-3766
doi: 10.1016/j.cclet.2021.11.008
Abstract:
The development of effective uranium-removal techniques is of great significance to the environment and human health. In this work, a double potential step technique (DPST) was applied to remove U(VI) from uranium-containing wastewater using a carbon felt electrode modified by graphene oxide/phytic acid composite (GO-PA@CF). The application of DPST can inhibit water splitting and prevent GO-PA from adsorbing other interfering ions in wastewater. The GO-PA composite can effectively accelerate the electrochemical reduction rate of U(VI), which significantly improved the electrochemical deposition rate of uranium oxide. As a result, the maximum removal efficiency and maximum removal capacity of GO-PA@CF electrode reached 98.7% and 1149.3 mg/g, respectively. The removal efficiency remained 97.2% after five cycles of reuse. Moreover, the removal efficiency of GO-PA@CF electrode can reach more than 70% in simulated wastewater.
The development of effective uranium-removal techniques is of great significance to the environment and human health. In this work, a double potential step technique (DPST) was applied to remove U(VI) from uranium-containing wastewater using a carbon felt electrode modified by graphene oxide/phytic acid composite (GO-PA@CF). The application of DPST can inhibit water splitting and prevent GO-PA from adsorbing other interfering ions in wastewater. The GO-PA composite can effectively accelerate the electrochemical reduction rate of U(VI), which significantly improved the electrochemical deposition rate of uranium oxide. As a result, the maximum removal efficiency and maximum removal capacity of GO-PA@CF electrode reached 98.7% and 1149.3 mg/g, respectively. The removal efficiency remained 97.2% after five cycles of reuse. Moreover, the removal efficiency of GO-PA@CF electrode can reach more than 70% in simulated wastewater.
2022, 33(8): 3767-3771
doi: 10.1016/j.cclet.2021.11.022
Abstract:
Aqueous phase synthesized ternary I–III–VI2 Quantum dots (QDs) are getting more and more attention in biology researches, for their good biocompatibility and easy-to-adjust fluorescence properties. However, the quantum yield (QY) of these aqueous phase synthesized QDs are often pretty low, which seriously hindered their further applications in this field. In general, the ripening of the QDs helps to enhance their QY, closely related to the ripening temperature. But it is still hard to precisely control the fluorescence performance of the QDs products, due to the difficulties in precise temperature control and cumbersome temperature adjusting operations in batch reactors. Here we proposed an integrated droplet microfluidic chip for the automated and successive AgInS2 QDs synthesis and ripening, with both temperatures controlled independently, precisely but easily. Taking advantage of the space-time transformation of the droplet microfluidic chips, the suitable temperature combination for AgInS2 QDs synthesis and ripening was studied, and the high-performance AgInS2 QDs were obtained. In addition, the reason for the decrease of QY of AgInS2 QDs at higher ripening temperature was also explored.
Aqueous phase synthesized ternary I–III–VI2 Quantum dots (QDs) are getting more and more attention in biology researches, for their good biocompatibility and easy-to-adjust fluorescence properties. However, the quantum yield (QY) of these aqueous phase synthesized QDs are often pretty low, which seriously hindered their further applications in this field. In general, the ripening of the QDs helps to enhance their QY, closely related to the ripening temperature. But it is still hard to precisely control the fluorescence performance of the QDs products, due to the difficulties in precise temperature control and cumbersome temperature adjusting operations in batch reactors. Here we proposed an integrated droplet microfluidic chip for the automated and successive AgInS2 QDs synthesis and ripening, with both temperatures controlled independently, precisely but easily. Taking advantage of the space-time transformation of the droplet microfluidic chips, the suitable temperature combination for AgInS2 QDs synthesis and ripening was studied, and the high-performance AgInS2 QDs were obtained. In addition, the reason for the decrease of QY of AgInS2 QDs at higher ripening temperature was also explored.
2022, 33(8): 3772-3776
doi: 10.1016/j.cclet.2021.12.008
Abstract:
RNA molecules contain diverse modifications that display important functions in a variety of physiological and pathological processes. So far over 150 chemical modifications have been characterized to be present in various RNA species, such as in messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). Previous studies revealed that certain RNA modifications were correlated to specific human diseases, indicating RNA modifications could serve as the potential indicator of human diseases. However, systemic investigation of the alteration of RNA modifications in different RNA species of carcinoma tissues are still lacked. Herein, we carried out the comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed method allowed us to simultaneously detect 48 different types of RNA modifications. Using this method, we detected 10, 15, 14, and 25 modifications in mRNA, 18S rRNA, 28S rRNA and small RNA (< 200 nt), respectively. Compared to the normal tissues, we revealed a total of 14 RNA modification exhibited significant increase and 2 RNA modifications showed significant decrease in thyroid carcinoma tissues. Our study provided the first comprehensive profile as well as the alteration of modifications in different RNA species in thyroid carcinoma and matched tumor-adjacent normal tissues. The altered pattern RNA modifications may serve as the indicator of thyroid carcinoma. Moreover, this study may promote the in-depth understanding of the regulatory roles of RNA modifications in thyroid carcinoma.
RNA molecules contain diverse modifications that display important functions in a variety of physiological and pathological processes. So far over 150 chemical modifications have been characterized to be present in various RNA species, such as in messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). Previous studies revealed that certain RNA modifications were correlated to specific human diseases, indicating RNA modifications could serve as the potential indicator of human diseases. However, systemic investigation of the alteration of RNA modifications in different RNA species of carcinoma tissues are still lacked. Herein, we carried out the comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed method allowed us to simultaneously detect 48 different types of RNA modifications. Using this method, we detected 10, 15, 14, and 25 modifications in mRNA, 18S rRNA, 28S rRNA and small RNA (< 200 nt), respectively. Compared to the normal tissues, we revealed a total of 14 RNA modification exhibited significant increase and 2 RNA modifications showed significant decrease in thyroid carcinoma tissues. Our study provided the first comprehensive profile as well as the alteration of modifications in different RNA species in thyroid carcinoma and matched tumor-adjacent normal tissues. The altered pattern RNA modifications may serve as the indicator of thyroid carcinoma. Moreover, this study may promote the in-depth understanding of the regulatory roles of RNA modifications in thyroid carcinoma.
2022, 33(8): 3777-3781
doi: 10.1016/j.cclet.2021.12.019
Abstract:
5-Hydroxymethylcytosine (5hmC), an intermediate product of DNA demethylation, is important for the regulation of gene expression during development and even tumorigenesis. The challenges associated with determination of 5hmC level include its extremely low abundance and high structural similarity with other cytosine derivatives, which resulted in sophisticated treatment with large amount of sample input. Herein, we developed a primer-initiated strand displacement amplification (PISDA) strategy to quantify the global 5hmC in genomic DNA from mammalian tissues with high sensitivity/selectivity, low input and simple operation. This sensitive fluorescence method is based on 5hmC-specific glucosylation, primer ligation and DNA amplification. After the primer was labeled on 5hmC site, DNA polymerase and nicking enzyme will repeatedly act on each primer, causing a significant increase of fluorescence signal to magnify the minor difference of 5hmC content from other cytosine derivatives. This method enables highly sensitive analysis of 5hmC with a detection limit of 0.003% in DNA (13.6 fmol, S/N = 3) from sample input of only 150 ng, which takes less than 15 min for determination. Further determination of 5hmC in different tissues not only confirms the widespread presence of 5hmC but also indicates its significant variation in different tissues and ages. Importantly, this PISDA strategy exhibits distinct advantages of bisulfite-free treatment, mild conditions and simple operation without the involvement of either expensive equipment or large amount of DNA sample. This method can be easily performed in almost all research and medical laboratories, and would provide a promising prospect to detect global 5hmC in mammalian tissues.
5-Hydroxymethylcytosine (5hmC), an intermediate product of DNA demethylation, is important for the regulation of gene expression during development and even tumorigenesis. The challenges associated with determination of 5hmC level include its extremely low abundance and high structural similarity with other cytosine derivatives, which resulted in sophisticated treatment with large amount of sample input. Herein, we developed a primer-initiated strand displacement amplification (PISDA) strategy to quantify the global 5hmC in genomic DNA from mammalian tissues with high sensitivity/selectivity, low input and simple operation. This sensitive fluorescence method is based on 5hmC-specific glucosylation, primer ligation and DNA amplification. After the primer was labeled on 5hmC site, DNA polymerase and nicking enzyme will repeatedly act on each primer, causing a significant increase of fluorescence signal to magnify the minor difference of 5hmC content from other cytosine derivatives. This method enables highly sensitive analysis of 5hmC with a detection limit of 0.003% in DNA (13.6 fmol, S/N = 3) from sample input of only 150 ng, which takes less than 15 min for determination. Further determination of 5hmC in different tissues not only confirms the widespread presence of 5hmC but also indicates its significant variation in different tissues and ages. Importantly, this PISDA strategy exhibits distinct advantages of bisulfite-free treatment, mild conditions and simple operation without the involvement of either expensive equipment or large amount of DNA sample. This method can be easily performed in almost all research and medical laboratories, and would provide a promising prospect to detect global 5hmC in mammalian tissues.
2022, 33(8): 3782-3786
doi: 10.1016/j.cclet.2021.11.012
Abstract:
Lanthanide-doped upconversion nanoparticles (Ln-UCNPs) are a new type of nanomaterials with excellent fluorescence properties, which are well applied in fluorescent biosensing. Herein we developed a multifunctional probe based on the surface engineering of core-shell structure UCNPs with polyacrylic acid (PAA). The developed PAA/UCNPs probe could be highly selective to detect and respond to Cu2+ at different pH. Cu2+ could easily combine with the carboxylate anion of PAA to quench the fluorescence of UCNPs. Therefore, we creatively proposed a fluorescent array sensor (PAA/UCNPs-Cu2+), in which the same material acted as the sensing element by coupled with pH regulation for pattern recognition of 5 thiols. It could also easily identify the chiral enantiomer of cystine (L-Cys-and D-Cys), and distinguish their mixed samples with different concentrations, and more importantly, it could be combined with urine samples to detect actual level of homocysteine (Hcys) to provide a new solution for judging whether the human body suffers from homocystinuria.
Lanthanide-doped upconversion nanoparticles (Ln-UCNPs) are a new type of nanomaterials with excellent fluorescence properties, which are well applied in fluorescent biosensing. Herein we developed a multifunctional probe based on the surface engineering of core-shell structure UCNPs with polyacrylic acid (PAA). The developed PAA/UCNPs probe could be highly selective to detect and respond to Cu2+ at different pH. Cu2+ could easily combine with the carboxylate anion of PAA to quench the fluorescence of UCNPs. Therefore, we creatively proposed a fluorescent array sensor (PAA/UCNPs-Cu2+), in which the same material acted as the sensing element by coupled with pH regulation for pattern recognition of 5 thiols. It could also easily identify the chiral enantiomer of cystine (L-Cys-and D-Cys), and distinguish their mixed samples with different concentrations, and more importantly, it could be combined with urine samples to detect actual level of homocysteine (Hcys) to provide a new solution for judging whether the human body suffers from homocystinuria.
2022, 33(8): 3787-3791
doi: 10.1016/j.cclet.2021.11.028
Abstract:
The construction of rich phase interfaces to increase active reaction area in hybrid materials is an excellent strategy to improve electrochemical performance. Under this guideline, MIL-101@OX-metal organic framework (MOF) is constructed by the "MOF on MOF" method, then converts to MIL-101@NiFe-layered double hydroxides (LDH) by in situ transformation in alkaline solution. MIL-101@NiFe-LDH shows excellent electrochemical water oxidation performance. It needs only an overpotential of 215 mV to drive 10 mA/cm2 of oxygen evolution reaction (OER), which is less than that of NiFe-LDH, MIL-101. In addition, MIL-101@NiFe-LDH has the smallest Tafel slope (55.1 mV/dec) compared with NiFe-LDH (61.1 mV/dec), MIL-101 (150.8 mV/dec). The excellent water oxidation activity is due to the high phase interfaces derived from high specific surface area of MOF. This work offers an alternative method for making MOF/LDH heterostructures with an optimized phase interfaces and provides new insights for OER.
The construction of rich phase interfaces to increase active reaction area in hybrid materials is an excellent strategy to improve electrochemical performance. Under this guideline, MIL-101@OX-metal organic framework (MOF) is constructed by the "MOF on MOF" method, then converts to MIL-101@NiFe-layered double hydroxides (LDH) by in situ transformation in alkaline solution. MIL-101@NiFe-LDH shows excellent electrochemical water oxidation performance. It needs only an overpotential of 215 mV to drive 10 mA/cm2 of oxygen evolution reaction (OER), which is less than that of NiFe-LDH, MIL-101. In addition, MIL-101@NiFe-LDH has the smallest Tafel slope (55.1 mV/dec) compared with NiFe-LDH (61.1 mV/dec), MIL-101 (150.8 mV/dec). The excellent water oxidation activity is due to the high phase interfaces derived from high specific surface area of MOF. This work offers an alternative method for making MOF/LDH heterostructures with an optimized phase interfaces and provides new insights for OER.
2022, 33(8): 3792-3796
doi: 10.1016/j.cclet.2021.11.031
Abstract:
Water pollution has become a serious problem owing to the development of society. Photocatalysis is a promising approach to remove various pollutants in water, such as organic pollutants and antibiotic resistance bacteria. Meanwhile, the design of heterojunction between two semiconductors is an effective path to improve photocatalytic properties due to its potential in improving separation and transfer of photoinduced carriers. In this study, Nb2O5/g-C3N4 (NO/CN) composite materials were prepared through a one-step heating method. Characterizations confirmed successful preparation of NO/CN heterojunction structure and better optical properties than pure g-C3N4 and Nb2O5. NO/CN composite materials showed excellent photocatalytic efficiency for Escherichia coli (E. coli) inactivation (95%) compared with the pure Nb2O5 (10%) and g-C3N4 (77%). Meanwhile, NO/CN exhibited better organic pollutants removal (RhB for 94%, methyl orange (MO) for 15% and methylene blue (MB) for 87%) under visible light, which is likely owing to the heterojunction structure between g-C3N4 and Nb2O5 that leads to the good separation of photogenerated electron-hole pair. Free radical scavenging and electron spin resonance (ESR) experiments demonstrated that superoxide radicals (•O2−) and holes (h+) were the dominant radicals. Therefore, the NO/CN was proposed to be a promising material for effective disinfection and removal of organic contaminants in water treatment.
Water pollution has become a serious problem owing to the development of society. Photocatalysis is a promising approach to remove various pollutants in water, such as organic pollutants and antibiotic resistance bacteria. Meanwhile, the design of heterojunction between two semiconductors is an effective path to improve photocatalytic properties due to its potential in improving separation and transfer of photoinduced carriers. In this study, Nb2O5/g-C3N4 (NO/CN) composite materials were prepared through a one-step heating method. Characterizations confirmed successful preparation of NO/CN heterojunction structure and better optical properties than pure g-C3N4 and Nb2O5. NO/CN composite materials showed excellent photocatalytic efficiency for Escherichia coli (E. coli) inactivation (95%) compared with the pure Nb2O5 (10%) and g-C3N4 (77%). Meanwhile, NO/CN exhibited better organic pollutants removal (RhB for 94%, methyl orange (MO) for 15% and methylene blue (MB) for 87%) under visible light, which is likely owing to the heterojunction structure between g-C3N4 and Nb2O5 that leads to the good separation of photogenerated electron-hole pair. Free radical scavenging and electron spin resonance (ESR) experiments demonstrated that superoxide radicals (•O2−) and holes (h+) were the dominant radicals. Therefore, the NO/CN was proposed to be a promising material for effective disinfection and removal of organic contaminants in water treatment.
2022, 33(8): 3797-3801
doi: 10.1016/j.cclet.2021.11.042
Abstract:
In this work, Z-scheme V2O5 loaded fluorinated inverse opal carbon nitride (IO F-CN/V2O5) was synthesized as a product of ternary collaborative modification with heterostructure construction, element doping and inverse opal structure. The catalyst presented the highest photocatalytic activity and rate constant for degradation of typical organic pollutants Rhodamine B (RhB) and was also used for the efficient removal of antibiotics, represented by norfloxacin (NOR), sulfadiazine (SD) and levofloxacin (LVX). Characterizations confirmed its increased specific surface area, narrowed bandgap, and enhanced visible light utilization capacity. Further mechanism study including band structure study and electron paramagnetic resonance (EPR) proved the successful construction of Z-scheme heterojunction, which improved photo-generated charge carrier migration and provide sufficient free radicals for the degradation process. The combination of different modifications contributed to the synergetic improvement of removal efficiency towards different organic pollutants.
In this work, Z-scheme V2O5 loaded fluorinated inverse opal carbon nitride (IO F-CN/V2O5) was synthesized as a product of ternary collaborative modification with heterostructure construction, element doping and inverse opal structure. The catalyst presented the highest photocatalytic activity and rate constant for degradation of typical organic pollutants Rhodamine B (RhB) and was also used for the efficient removal of antibiotics, represented by norfloxacin (NOR), sulfadiazine (SD) and levofloxacin (LVX). Characterizations confirmed its increased specific surface area, narrowed bandgap, and enhanced visible light utilization capacity. Further mechanism study including band structure study and electron paramagnetic resonance (EPR) proved the successful construction of Z-scheme heterojunction, which improved photo-generated charge carrier migration and provide sufficient free radicals for the degradation process. The combination of different modifications contributed to the synergetic improvement of removal efficiency towards different organic pollutants.
2022, 33(8): 3802-3808
doi: 10.1016/j.cclet.2021.11.037
Abstract:
Remarkable Li-ion battery (LIB) anode materials need to have long cycle life and fast charge/discharge rate, however they are difficult to be realized in the monolayer anode materials. The monolayer β-Bi has the stiffness of only 33.0 N/m, thus the Bi/G heterostructure is proposed to improve the electronic and mechanical properties and to produce better LIB anode performance in this paper. The calculated results show that Bi/G heterostructure has excellent thermodynamic, dynamical and mechanical stability. The band gap is only 0.04 eV, which ensures remarkable electrical conductivity. In addition, the Bi/G heterostructure has higher stiffness (369.2 N/m) than that of monolayer β-Bi and graphene. The diffusion barrier (Ebarrier) of 0.32 eV and volume expansion ratio (VER) of only 4% can ensure the rapid transport of Li+ ions in the charge/discharge cycling process and long life of the LIB. These calculated theoretical results for describing the detail properties of Li storage and diffusion in the Bi/G heterostructure can supply adequate conclusive evidence for the prediction of remarkable properties of Bi/G heterostructure as an anode material for LIBs.
Remarkable Li-ion battery (LIB) anode materials need to have long cycle life and fast charge/discharge rate, however they are difficult to be realized in the monolayer anode materials. The monolayer β-Bi has the stiffness of only 33.0 N/m, thus the Bi/G heterostructure is proposed to improve the electronic and mechanical properties and to produce better LIB anode performance in this paper. The calculated results show that Bi/G heterostructure has excellent thermodynamic, dynamical and mechanical stability. The band gap is only 0.04 eV, which ensures remarkable electrical conductivity. In addition, the Bi/G heterostructure has higher stiffness (369.2 N/m) than that of monolayer β-Bi and graphene. The diffusion barrier (Ebarrier) of 0.32 eV and volume expansion ratio (VER) of only 4% can ensure the rapid transport of Li+ ions in the charge/discharge cycling process and long life of the LIB. These calculated theoretical results for describing the detail properties of Li storage and diffusion in the Bi/G heterostructure can supply adequate conclusive evidence for the prediction of remarkable properties of Bi/G heterostructure as an anode material for LIBs.
2022, 33(8): 3809-3817
doi: 10.1016/j.cclet.2021.11.061
Abstract:
The natural hematite (α-Fe2O3) is stable and abundant on the earth, as well as with strange electronic band structure and good visible light absorption properties. However, the composition and catalytic performance of natural hematite should be explored. In this study, the photo-assisted hematite nanoparticles activated persulfate (H-NPs/PS/vis) system was constructed. As detected, H-NPs had an irregular agglomerate structure with abundant internal pore and were mainly composed of Fe2O3, SiO2 and TiO2. The system was applied to removing various antibiotic (i.e., lomefloxacin, ciprofloxacin and enrofloxacin with initial concentration of 10 mg/L), achieving high degradation performance of 82.0%, 81.2% and 82.2% after 120, 330 and 240 min, respectively. Moreover, H-NPs had excellent reusability with low metal leaching (Ti leaching percentage lower than 0.01%, Fe dissolution percentage was 0.48%) and stable structure. At last, a possible reaction mechanism of H-NPs/PS/vis system was proposed that lomefloxacin (LOM) was efficiently removed via the synergistic process of components contained in H-NPs with PS and light, involving the generation of •O2−, •OH and SO4•−. Above all, this paper provided a novel application scheme of natural hematite through in-depth and comprehensive experimental exploration.
The natural hematite (α-Fe2O3) is stable and abundant on the earth, as well as with strange electronic band structure and good visible light absorption properties. However, the composition and catalytic performance of natural hematite should be explored. In this study, the photo-assisted hematite nanoparticles activated persulfate (H-NPs/PS/vis) system was constructed. As detected, H-NPs had an irregular agglomerate structure with abundant internal pore and were mainly composed of Fe2O3, SiO2 and TiO2. The system was applied to removing various antibiotic (i.e., lomefloxacin, ciprofloxacin and enrofloxacin with initial concentration of 10 mg/L), achieving high degradation performance of 82.0%, 81.2% and 82.2% after 120, 330 and 240 min, respectively. Moreover, H-NPs had excellent reusability with low metal leaching (Ti leaching percentage lower than 0.01%, Fe dissolution percentage was 0.48%) and stable structure. At last, a possible reaction mechanism of H-NPs/PS/vis system was proposed that lomefloxacin (LOM) was efficiently removed via the synergistic process of components contained in H-NPs with PS and light, involving the generation of •O2−, •OH and SO4•−. Above all, this paper provided a novel application scheme of natural hematite through in-depth and comprehensive experimental exploration.
2022, 33(8): 3818-3822
doi: 10.1016/j.cclet.2021.11.071
Abstract:
In this work, a conductive thin film composite forward osmosis (TFC-FO) membrane was firstly prepared via vacuum filtering MXenes nanolayer on the outer surface of polyethersulfone membrane followed by interfacial polymerization in the other side. Moreover, its feasibility of mitigating organic fouling under electric field was evaluated. Results indicated that the addition of MXenes greatly reduced the electric resistance of membrane from 2.1 × 1012 Ω to 46.8 Ω, enhanced the membrane porosity and promoted the membrane performance in terms of the ratio of water flux to reverse salt flux. The modified TFC-FO membrane presented the optimal performance with 0.47 g/m2 loading amount of MXenes. Organic fouling experiments using sodium alginate (SA) and bovine serum albumin (BSA) as representative demonstrated that the introduction of MXenes could effectively enhance the anti-fouling ability of TFC-FO membrane under the electric field of 2 V. The interelectron repulsion hindered organic foulants attaching into membrane surface and thus effectively alleviated the membrane fouling. More importantly, the modified TFC-FO membrane showed good stability during the fouling experiment of 10 h. In all, our work proved that introducing MXenes into the porous layer of support is feasible to alleviate organic fouling of FO membrane.
In this work, a conductive thin film composite forward osmosis (TFC-FO) membrane was firstly prepared via vacuum filtering MXenes nanolayer on the outer surface of polyethersulfone membrane followed by interfacial polymerization in the other side. Moreover, its feasibility of mitigating organic fouling under electric field was evaluated. Results indicated that the addition of MXenes greatly reduced the electric resistance of membrane from 2.1 × 1012 Ω to 46.8 Ω, enhanced the membrane porosity and promoted the membrane performance in terms of the ratio of water flux to reverse salt flux. The modified TFC-FO membrane presented the optimal performance with 0.47 g/m2 loading amount of MXenes. Organic fouling experiments using sodium alginate (SA) and bovine serum albumin (BSA) as representative demonstrated that the introduction of MXenes could effectively enhance the anti-fouling ability of TFC-FO membrane under the electric field of 2 V. The interelectron repulsion hindered organic foulants attaching into membrane surface and thus effectively alleviated the membrane fouling. More importantly, the modified TFC-FO membrane showed good stability during the fouling experiment of 10 h. In all, our work proved that introducing MXenes into the porous layer of support is feasible to alleviate organic fouling of FO membrane.
2022, 33(8): 3823-3828
doi: 10.1016/j.cclet.2021.11.068
Abstract:
Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability, and the use of manganese dioxide (MnO2) to facilitate Pd reduction of organic pollutants is just started. However, there is still a limited understanding of how to match the Pd load and MnO2 to realize optimal dechlorination efficiency at minimum cost. Here, a Pd/MnO2/Ni foam cathode was successfully fabricated and applied for the efficient electrochemical dechlorination of 2, 4, 6-trichlorophenol (2, 4, 6-TCP). The optimal electrocatalytic hydrodechlorination (ECH) performance with 2, 4, 6-TCP dechlorination efficiency (92.58% in 180 min) was obtained when the concentration of PdCl2 precipitation was 1 mmol/L, the deposition time of MnO2 was 300 s and cathode potential was −0.8 V. Performance influenced by the exogenous factors (e.g., initial pH and coexisted ions) were further investigated. It was found that the neutral pH was the most favorable for ECH and a reduction in dechlorination efficiency (6%~47.6%) was observed in presence of 5 mmol/L of NO2−, NO3−, S2− or SO32−. Cyclic voltammetry (CV) and quenching experiments verified the existence of three hydrogen species on Pd surface, including adsorbed atomic hydrogen (H*ads), absorbed atomic hydrogen (H*abs), and molecular hydrogen (H2). And the introduction of MnO2 promoted the generation of atomic H*. Only adsorbed atomic hydrogen (H*ads) was confirmed that it truly facilitated the ECH process. Besides H*ads induced reduction, the direct reduction by cathode electrons also participated in the 2, 4, 6-TCP dechlorination process. Pd/MnO2/Ni foam cathode shows excellent dechlorination performance, fine stability and recyclable potential, which provides strategies for the effective degradation of persistent halogenated organic pollutants in groundwater.
Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability, and the use of manganese dioxide (MnO2) to facilitate Pd reduction of organic pollutants is just started. However, there is still a limited understanding of how to match the Pd load and MnO2 to realize optimal dechlorination efficiency at minimum cost. Here, a Pd/MnO2/Ni foam cathode was successfully fabricated and applied for the efficient electrochemical dechlorination of 2, 4, 6-trichlorophenol (2, 4, 6-TCP). The optimal electrocatalytic hydrodechlorination (ECH) performance with 2, 4, 6-TCP dechlorination efficiency (92.58% in 180 min) was obtained when the concentration of PdCl2 precipitation was 1 mmol/L, the deposition time of MnO2 was 300 s and cathode potential was −0.8 V. Performance influenced by the exogenous factors (e.g., initial pH and coexisted ions) were further investigated. It was found that the neutral pH was the most favorable for ECH and a reduction in dechlorination efficiency (6%~47.6%) was observed in presence of 5 mmol/L of NO2−, NO3−, S2− or SO32−. Cyclic voltammetry (CV) and quenching experiments verified the existence of three hydrogen species on Pd surface, including adsorbed atomic hydrogen (H*ads), absorbed atomic hydrogen (H*abs), and molecular hydrogen (H2). And the introduction of MnO2 promoted the generation of atomic H*. Only adsorbed atomic hydrogen (H*ads) was confirmed that it truly facilitated the ECH process. Besides H*ads induced reduction, the direct reduction by cathode electrons also participated in the 2, 4, 6-TCP dechlorination process. Pd/MnO2/Ni foam cathode shows excellent dechlorination performance, fine stability and recyclable potential, which provides strategies for the effective degradation of persistent halogenated organic pollutants in groundwater.
2022, 33(8): 3829-3834
doi: 10.1016/j.cclet.2021.12.004
Abstract:
Peroxymonosulfate (PMS) activation in heterogeneous processes is a promising water treatment technology. Nevertheless, the high energy consumption and low efficiency during the reaction are ineluctable, due to electron cycling rate limitation. Herein, a new strategy is proposed based on a quantum dots (QDs)/PMS system. Co-ZnS QDs are synthesized by a water phase coprecipitation method. The inequivalent lattice-doping of Co for Zn leads to the generation of surface sulfur vacancies (SVs), which modulates the surface of the catalyst to form an electronic nonequilibrium surface. Astonishingly, the plasticizer micropollutants can be completely degraded within only tens of seconds in the Co-ZnS QDs/PMS system due to this type of surface modulation. The interfacial reaction mechanism is revealed that pollutants tend to be adsorbed on the cobalt metal sites as the electron donors, where the internal electrons of pollutants are captured by the metal species and transferred to the surface SVs. Meanwhile, PMS adsorbed on the SVs is reduced to radicals by capturing electrons, achieving effective electron recovery. Dissolved oxygen (DO) molecules are also easily attracted to catalyst defects and are reduced to O2•−, further promoting the degradation of pollutants.
Peroxymonosulfate (PMS) activation in heterogeneous processes is a promising water treatment technology. Nevertheless, the high energy consumption and low efficiency during the reaction are ineluctable, due to electron cycling rate limitation. Herein, a new strategy is proposed based on a quantum dots (QDs)/PMS system. Co-ZnS QDs are synthesized by a water phase coprecipitation method. The inequivalent lattice-doping of Co for Zn leads to the generation of surface sulfur vacancies (SVs), which modulates the surface of the catalyst to form an electronic nonequilibrium surface. Astonishingly, the plasticizer micropollutants can be completely degraded within only tens of seconds in the Co-ZnS QDs/PMS system due to this type of surface modulation. The interfacial reaction mechanism is revealed that pollutants tend to be adsorbed on the cobalt metal sites as the electron donors, where the internal electrons of pollutants are captured by the metal species and transferred to the surface SVs. Meanwhile, PMS adsorbed on the SVs is reduced to radicals by capturing electrons, achieving effective electron recovery. Dissolved oxygen (DO) molecules are also easily attracted to catalyst defects and are reduced to O2•−, further promoting the degradation of pollutants.
2022, 33(8): 3835-3841
doi: 10.1016/j.cclet.2021.12.025
Abstract:
The solar-driven photocatalytic technology has shown great potential in nitrate (NO3−) pollutants reduction, however, it has been greatly hindered by the complex preparation and high cost of photocatalysts. Herein, a relatively low-cost photocatalyst, rutile and anatase mixed phase TiO2 was synthesized by a facile microwave-hydrothermal method. Meanwhile, oxygen vacancy is successfully generated, leading to an acidic surface for strong adsorption towards NO3−, which further improved the reduction activity. Compared with the commercial P25, a higher NO3− conversion of ca. 100% and nitrogen (N2) selectivity of 87% were achieved under UV (365 nm) irradiation within 2 h. This research provides a promising strategy for designing efficient noble metal free photocatalyst in the NO3− reduction.
The solar-driven photocatalytic technology has shown great potential in nitrate (NO3−) pollutants reduction, however, it has been greatly hindered by the complex preparation and high cost of photocatalysts. Herein, a relatively low-cost photocatalyst, rutile and anatase mixed phase TiO2 was synthesized by a facile microwave-hydrothermal method. Meanwhile, oxygen vacancy is successfully generated, leading to an acidic surface for strong adsorption towards NO3−, which further improved the reduction activity. Compared with the commercial P25, a higher NO3− conversion of ca. 100% and nitrogen (N2) selectivity of 87% were achieved under UV (365 nm) irradiation within 2 h. This research provides a promising strategy for designing efficient noble metal free photocatalyst in the NO3− reduction.
2022, 33(8): 3842-3848
doi: 10.1016/j.cclet.2021.11.030
Abstract:
As an important anode material for fast-charging Li-ion batteries (LIBs), black phosphorus (BP) has attracted extensive attention. Black phosphorene nanotubes (BPNTs) can be theoretically produced by rolling up the black phosphorene nanosheet along armchair (a-BPNTs) and zigzag (z-BPNTs) directions. The effects of curvature, chirality, Li-storage concentrations and strain stress on the Li-storage performance such as Li diffusion barriers and mechanical stabilities of BPNTs are mainly investigated by first principles calculations. The theoretical calculations predict that the a-BPNTs and z-BPNTs have good maximum Li-storage capacities, and the z-BPNTs exhibit better flexibility than a-BPNTs. The mechanical stabilities and Li-migration are all related to the curvature of BPNTs. Additionally, both a-BPNTs and z-BPNTs exhibit fast Li-ion conductivity along the c-axis direction. Moreover, the average Poisson's ratio of a-BPNTs (0.68) is larger than that of z-BPNTs (0.17), indicating that the strain stress is more difficult to apply on a-BPNTs than z-BPNTs. Our calculations predict that the a-BPNTs can afford ultrafast kinetic rate for fast-charging and high-power LIBs, while the z-BPNTs can provide extra capacity for high-energy LIBs.
As an important anode material for fast-charging Li-ion batteries (LIBs), black phosphorus (BP) has attracted extensive attention. Black phosphorene nanotubes (BPNTs) can be theoretically produced by rolling up the black phosphorene nanosheet along armchair (a-BPNTs) and zigzag (z-BPNTs) directions. The effects of curvature, chirality, Li-storage concentrations and strain stress on the Li-storage performance such as Li diffusion barriers and mechanical stabilities of BPNTs are mainly investigated by first principles calculations. The theoretical calculations predict that the a-BPNTs and z-BPNTs have good maximum Li-storage capacities, and the z-BPNTs exhibit better flexibility than a-BPNTs. The mechanical stabilities and Li-migration are all related to the curvature of BPNTs. Additionally, both a-BPNTs and z-BPNTs exhibit fast Li-ion conductivity along the c-axis direction. Moreover, the average Poisson's ratio of a-BPNTs (0.68) is larger than that of z-BPNTs (0.17), indicating that the strain stress is more difficult to apply on a-BPNTs than z-BPNTs. Our calculations predict that the a-BPNTs can afford ultrafast kinetic rate for fast-charging and high-power LIBs, while the z-BPNTs can provide extra capacity for high-energy LIBs.
2022, 33(8): 3849-3852
doi: 10.1016/j.cclet.2021.10.030
Abstract:
Owing to frequent environmental monitoring of tetrabromobisphenol-A (TBBPA) analogs and their potential ecotoxicological effects on organisms, analysis of trace levels of TBBPA analogs with more non-polar and less water-soluble characteristics is of great significance for studying their environmental behaviors and toxic effects. Herein, a fast and sensitive technique is developed for directly detecting aqueous TBBPA analogs, including TBBPA mono(allyl ether) (TBBPA-MAE), TBBPA mono(2,3-dibromopropyl ether) (TBBPA-MDBPE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE) and TBBPA mono(glycidyl ether) (TBBPA-MGE), by combining solid phase microextraction (SPME) based on porous covalent organic frameworks (Porous-COFs) with constant flow desorption ionization-mass spectrometry (CFDI-MS). As chromatographic separation is replaced by constant flow desorption, each sample can be analyzed within 7 min. The hierarchical porous structures (microporous, mesoporous and macroporous) of COFs lead to the enhanced mass transfer and the easier accessibility of active sites to TBBPA analogs, so that the extraction efficiency is 2.3–3.6 times higher than pure microporous COFs, and far superior to commercial coatings. The detection limit and quantification limit of this method are 0.1–1 and 0.4–3.2 ng/L, respectively. Ultra-trace levels of TBBPA analogs from 5.0 ng/L to 66 ng/L have been successfully detected in river and sea water samples, showing great potential for subsequent studies of their environmental behaviors and toxicological effects
Owing to frequent environmental monitoring of tetrabromobisphenol-A (TBBPA) analogs and their potential ecotoxicological effects on organisms, analysis of trace levels of TBBPA analogs with more non-polar and less water-soluble characteristics is of great significance for studying their environmental behaviors and toxic effects. Herein, a fast and sensitive technique is developed for directly detecting aqueous TBBPA analogs, including TBBPA mono(allyl ether) (TBBPA-MAE), TBBPA mono(2,3-dibromopropyl ether) (TBBPA-MDBPE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE) and TBBPA mono(glycidyl ether) (TBBPA-MGE), by combining solid phase microextraction (SPME) based on porous covalent organic frameworks (Porous-COFs) with constant flow desorption ionization-mass spectrometry (CFDI-MS). As chromatographic separation is replaced by constant flow desorption, each sample can be analyzed within 7 min. The hierarchical porous structures (microporous, mesoporous and macroporous) of COFs lead to the enhanced mass transfer and the easier accessibility of active sites to TBBPA analogs, so that the extraction efficiency is 2.3–3.6 times higher than pure microporous COFs, and far superior to commercial coatings. The detection limit and quantification limit of this method are 0.1–1 and 0.4–3.2 ng/L, respectively. Ultra-trace levels of TBBPA analogs from 5.0 ng/L to 66 ng/L have been successfully detected in river and sea water samples, showing great potential for subsequent studies of their environmental behaviors and toxicological effects
2022, 33(8): 3853-3858
doi: 10.1016/j.cclet.2021.10.045
Abstract:
Surface-enhanced Raman scattering (SERS) spectroscopy has been employed as a rapid analysis technology for food security inspection recently. Nowadays, it is still a great challenge to rapidly quantify multiple trace antibiotics potentially abused in aquaculture industry. In this work, a magnetic Ti3C2Tx/Fe3O4/Ag substrate was prepared for the development of a reliable rapid SERS quantification method for multiple trace sulfonamides in aquatic products. This magnetic substrate had good uniformity, reproducibility, stability and SERS activity. Moreover, this substrate could integrate the magnetic separation-enrichment and matrix clean-up without cross contamination, which endowed it with good selectivity and anti-interference capability during real sample analysis. The electromagnetic enhancement and chemical enhancement mechanism of this magnetic substrate were studied in detail to reveal its good separation-enrichment performance and SERS activity. Finally, a rapid SERS quantification method was established and practically applied for trace phthalic sulfathiazole (PST) and silver sulfadiazine (SSD) in aquatic products by using Ti3C2Tx/Fe3O4/Ag magnetic substrates. Trace PST and SSD could be actually detected and quantified as 55.9 µg/kg and 64.0 µg/kg in aquatic products, respectively. Good recoveries of 83.9%–116% with relative standard deviations (RSDs) of 0.5%–3.2% for PST and 80.2%–102% with RSDs of 1.3%–5.8% for SSD were obtained. This work proposed an efficient and reliable method for rapid quantification of trace multiple sulfonamides in complex aquatic samples during food security inspection.
Surface-enhanced Raman scattering (SERS) spectroscopy has been employed as a rapid analysis technology for food security inspection recently. Nowadays, it is still a great challenge to rapidly quantify multiple trace antibiotics potentially abused in aquaculture industry. In this work, a magnetic Ti3C2Tx/Fe3O4/Ag substrate was prepared for the development of a reliable rapid SERS quantification method for multiple trace sulfonamides in aquatic products. This magnetic substrate had good uniformity, reproducibility, stability and SERS activity. Moreover, this substrate could integrate the magnetic separation-enrichment and matrix clean-up without cross contamination, which endowed it with good selectivity and anti-interference capability during real sample analysis. The electromagnetic enhancement and chemical enhancement mechanism of this magnetic substrate were studied in detail to reveal its good separation-enrichment performance and SERS activity. Finally, a rapid SERS quantification method was established and practically applied for trace phthalic sulfathiazole (PST) and silver sulfadiazine (SSD) in aquatic products by using Ti3C2Tx/Fe3O4/Ag magnetic substrates. Trace PST and SSD could be actually detected and quantified as 55.9 µg/kg and 64.0 µg/kg in aquatic products, respectively. Good recoveries of 83.9%–116% with relative standard deviations (RSDs) of 0.5%–3.2% for PST and 80.2%–102% with RSDs of 1.3%–5.8% for SSD were obtained. This work proposed an efficient and reliable method for rapid quantification of trace multiple sulfonamides in complex aquatic samples during food security inspection.
2022, 33(8): 3859-3864
doi: 10.1016/j.cclet.2021.12.017
Abstract:
Superwetting membranes have emerged as promising materials for the efficient treatment of oily wastewater. Typically, superwetting membranes can be developed by ingeniously chemical modification and topographical structuration of microporous membranes. Herein, we report the hierarchical assembly of metal-phenolic-polyplex coating to manipulate membrane surface superwettability by integrating metal-phenolic (FeⅢ-tannic acid (TA)) assembly with polyplex (tannic acid-polyethylenimine (PEI)) assembly. The proposed Fe-TA-PEI coating can be deposited on microporous membrane via simply dipping into FeⅢ-TA-PEI co-assembly solution. Based on the catechol chemistry, the coordination complexation of FeⅢ and TA develops metal-phenolic networks to provide hydrophilic chemistries, and the electrostatic complexation of TA and PEI generates nanoconjugates to impart hierarchical architectures. Benefiting from the synergy of hydrophilic chemistries and hierarchical architectures, the resulting PVDF/Fe-TA-PEI membrane exhibits excellent superhydrophilicity (~0°), underwater superoleophobicity (~150°) and superior anti-oil-adhesion capability. The superhydrophilicity of PVDF/Fe-TA-PEI membrane greatly promotes membrane permeability, featuring water fluxes up to 5860 L m−2 h−1. The underwater superoleophobicity of PVDF/Fe-TA-PEI membrane promises potential flux (3393 L m−2 h−1), high separation efficiency (99.3%) and desirable antifouling capability for oil-in-water emulsion separation. Thus, we highlight the reported hierarchical metal-phenolic-polyplex assembly as a straightforward and effective strategy that enables the synchronous modulation of surface chemistry and topography toward superwetting membranes for promising high-flux and antifouling oil-water separation.
Superwetting membranes have emerged as promising materials for the efficient treatment of oily wastewater. Typically, superwetting membranes can be developed by ingeniously chemical modification and topographical structuration of microporous membranes. Herein, we report the hierarchical assembly of metal-phenolic-polyplex coating to manipulate membrane surface superwettability by integrating metal-phenolic (FeⅢ-tannic acid (TA)) assembly with polyplex (tannic acid-polyethylenimine (PEI)) assembly. The proposed Fe-TA-PEI coating can be deposited on microporous membrane via simply dipping into FeⅢ-TA-PEI co-assembly solution. Based on the catechol chemistry, the coordination complexation of FeⅢ and TA develops metal-phenolic networks to provide hydrophilic chemistries, and the electrostatic complexation of TA and PEI generates nanoconjugates to impart hierarchical architectures. Benefiting from the synergy of hydrophilic chemistries and hierarchical architectures, the resulting PVDF/Fe-TA-PEI membrane exhibits excellent superhydrophilicity (~0°), underwater superoleophobicity (~150°) and superior anti-oil-adhesion capability. The superhydrophilicity of PVDF/Fe-TA-PEI membrane greatly promotes membrane permeability, featuring water fluxes up to 5860 L m−2 h−1. The underwater superoleophobicity of PVDF/Fe-TA-PEI membrane promises potential flux (3393 L m−2 h−1), high separation efficiency (99.3%) and desirable antifouling capability for oil-in-water emulsion separation. Thus, we highlight the reported hierarchical metal-phenolic-polyplex assembly as a straightforward and effective strategy that enables the synchronous modulation of surface chemistry and topography toward superwetting membranes for promising high-flux and antifouling oil-water separation.
2022, 33(8): 3865-3868
doi: 10.1016/j.cclet.2021.10.032
Abstract:
Nuclear RNA export into the cytoplasm is one of the key steps in protein expression to realize biological functions. Despite the broad availability of nucleic acid dyes, tracking and quantifying the highly dynamic process of RNA export in live cells is challenging. When dye-labeled RNA enters the cytoplasm, the dye molecules are released upon degradation of the RNA, allowing them to re-enter the cell nucleus. As a result, the ratio between the dye exported with RNA into the cytoplasm and the portion staying inside the nucleus cannot be determined. To address this common limitation, we report the design of a smart probe that can only check into the nucleus once. When adding to cells, this probe rapidly binds with nuclear RNAs in live cells and reacts with intrinsic H2S. This reaction not only activates the fluorescence for RNA tracking but also changes the structure of probe and consequently its intracellular localization. After disassociating from exported RNAs in cytoplasm, the probe preferentially enters lysosomes rather than cell nucleus, enabling real-time quantitative measurement of nuclear RNA exports. Using this probe, we successfully evaluated the effects of hormones and cancer drugs on nuclear RNA export in live cells. Interestingly, we found that hormones inhibiting RNA exports can partially offset the effect of chemotherapy.
Nuclear RNA export into the cytoplasm is one of the key steps in protein expression to realize biological functions. Despite the broad availability of nucleic acid dyes, tracking and quantifying the highly dynamic process of RNA export in live cells is challenging. When dye-labeled RNA enters the cytoplasm, the dye molecules are released upon degradation of the RNA, allowing them to re-enter the cell nucleus. As a result, the ratio between the dye exported with RNA into the cytoplasm and the portion staying inside the nucleus cannot be determined. To address this common limitation, we report the design of a smart probe that can only check into the nucleus once. When adding to cells, this probe rapidly binds with nuclear RNAs in live cells and reacts with intrinsic H2S. This reaction not only activates the fluorescence for RNA tracking but also changes the structure of probe and consequently its intracellular localization. After disassociating from exported RNAs in cytoplasm, the probe preferentially enters lysosomes rather than cell nucleus, enabling real-time quantitative measurement of nuclear RNA exports. Using this probe, we successfully evaluated the effects of hormones and cancer drugs on nuclear RNA export in live cells. Interestingly, we found that hormones inhibiting RNA exports can partially offset the effect of chemotherapy.
2022, 33(8): 3869-3872
doi: 10.1016/j.cclet.2021.10.048
Abstract:
Here, silica microspheres were decorated with two-dimensional metal–organic frameworks (2D MOFs) nanosheets and ionic liquids, and evaluated as the mixed-mode stationary phase for chromatographic separation. The ionic liquids were used to assist the synthesis of 2D MOFs nanosheets, and also acted as adhesives among the nanosheets and silica. In contrast with the 2D MOFs-based column without ionic liquids and commercial columns, the prepared column exhibited enhanced chromatographic separation performance for partially hydrophilic compounds such as alkaloids, sulfonamides and antibiotics, etc. In addition to excellent chromatographic repeatability and stability, it has also been verified that the composites could be easily and repeatedly prepared. The relative standard deviation of the retention time of the same type of analyte between the three batches of materials was ranging from 0.21% to 1.7%. In short, these results indicated that the synthesized composites were promising separation material for liquid chromatography, which made it possible to broaden the application of 2D MOFs in the field of chromatography.
Here, silica microspheres were decorated with two-dimensional metal–organic frameworks (2D MOFs) nanosheets and ionic liquids, and evaluated as the mixed-mode stationary phase for chromatographic separation. The ionic liquids were used to assist the synthesis of 2D MOFs nanosheets, and also acted as adhesives among the nanosheets and silica. In contrast with the 2D MOFs-based column without ionic liquids and commercial columns, the prepared column exhibited enhanced chromatographic separation performance for partially hydrophilic compounds such as alkaloids, sulfonamides and antibiotics, etc. In addition to excellent chromatographic repeatability and stability, it has also been verified that the composites could be easily and repeatedly prepared. The relative standard deviation of the retention time of the same type of analyte between the three batches of materials was ranging from 0.21% to 1.7%. In short, these results indicated that the synthesized composites were promising separation material for liquid chromatography, which made it possible to broaden the application of 2D MOFs in the field of chromatography.
2022, 33(8): 3873-3878
doi: 10.1016/j.cclet.2021.11.081
Abstract:
Chiral recognition of essential amino acids (EAAs) is a huge challenge that keeps plaguing analytical scientists due to their cryptochirality and limited steric interaction sites. Inspired by the superior enantioselectivity of functional supramolecular cyclodextrins (CDs) and strong signal amplification ability of field effect transistors (FETs), this work firstly reports a cationic supramolecular charge switch for facile enantiodiscrimination of EAAs based on extended-gate organic FET (EG-OFET). The cationic phenylcarbamoylated-CD single isomer acts as a charge switch via interacting with different enantiomers and the weak stereo-differentiation intermolecular interaction signals between the cationic perphenylcarbamoylated CDs and EAAs on the EG can be strongly and rapidly amplified through an OFET. Efficient chiral differentiation of six EAAs, including phenylalanine, tryptophan, leucine, isoleucine, lysine and valine, are successfully achieved without any derivation process and the detection limit for D-phenylalanine is down to 10−13 mol/L. We believe that this study provides a new and facile sensing perspective for natural amino acids and may afford deeper understanding of molecular chirality.
Chiral recognition of essential amino acids (EAAs) is a huge challenge that keeps plaguing analytical scientists due to their cryptochirality and limited steric interaction sites. Inspired by the superior enantioselectivity of functional supramolecular cyclodextrins (CDs) and strong signal amplification ability of field effect transistors (FETs), this work firstly reports a cationic supramolecular charge switch for facile enantiodiscrimination of EAAs based on extended-gate organic FET (EG-OFET). The cationic phenylcarbamoylated-CD single isomer acts as a charge switch via interacting with different enantiomers and the weak stereo-differentiation intermolecular interaction signals between the cationic perphenylcarbamoylated CDs and EAAs on the EG can be strongly and rapidly amplified through an OFET. Efficient chiral differentiation of six EAAs, including phenylalanine, tryptophan, leucine, isoleucine, lysine and valine, are successfully achieved without any derivation process and the detection limit for D-phenylalanine is down to 10−13 mol/L. We believe that this study provides a new and facile sensing perspective for natural amino acids and may afford deeper understanding of molecular chirality.
2022, 33(8): 3879-3882
doi: 10.1016/j.cclet.2021.12.059
Abstract:
The multiple sensing provides booming options to eliminate interference and ensure the accuracy of detection by mutually coupling and validating multiple data sets. Here, we integrate the jigsaw-like multifunctional mini-pillar platform to perform multi-mode (electrochemical, fluorescence, surface-enhanced Raman scattering (SERS) and colorimetric) sensing in individual microdroplets. Each mini-pillar connector can parallelize together by specific concave-convex interface to form integrated jigsaw-like platform for multi-mode sensing, and each specific mini-pillar can be modified into the individual sensing unit to read the prescribed signals. We successfully implemented electrochemical, fluorescence, SERS and colorimetric detection by multiple signals coupling to reduce the false positive analysis. Such platform brings a promising clue of in-situ analysis and point-of-care testing for disease diagnosis and health monitoring.
The multiple sensing provides booming options to eliminate interference and ensure the accuracy of detection by mutually coupling and validating multiple data sets. Here, we integrate the jigsaw-like multifunctional mini-pillar platform to perform multi-mode (electrochemical, fluorescence, surface-enhanced Raman scattering (SERS) and colorimetric) sensing in individual microdroplets. Each mini-pillar connector can parallelize together by specific concave-convex interface to form integrated jigsaw-like platform for multi-mode sensing, and each specific mini-pillar can be modified into the individual sensing unit to read the prescribed signals. We successfully implemented electrochemical, fluorescence, SERS and colorimetric detection by multiple signals coupling to reduce the false positive analysis. Such platform brings a promising clue of in-situ analysis and point-of-care testing for disease diagnosis and health monitoring.
2022, 33(8): 3883-3888
doi: 10.1016/j.cclet.2021.11.057
Abstract:
Designing a carbon material with a unique composition and surface functional groups for offering high specific capacity in a wide voltage window is of great significance to improve the energy density for the supercapacitor in a cheap and eco-friendly aqueous electrolyte. Herein, we develop an efficient strategy to synthesize a N, O co-doped hierarchically porous carbon (NODPC-1.0) with moderate specific surface area and pore volume as well as rich heteroatoms using a deep eutectic solvent (DES) as an activator. It is found that NODPC-1.0 with a large proportion of pseudocapacitive functional groups (pyrrole-N, pyridine-N and carbonyl-quinone) can work stable in an acidic 2 mol/L Li2SO4 (pH 2.5) electrolyte, exhibiting specific capacities of 375 and 186 F/g at the current densities of 1.0 and 100 A/g, respectively. Also, the assembled symmetric capacitor using the NODPC-1.0 as the active material and 2 mol/L acidic Li2SO4 (pH 2.5) as the electrolyte shows an outstanding energy density of 74.4 Wh/kg at a high power density of 1.44 kW/kg under a broad voltage window (2.4 V). Relevant comparative experiments indicate that H+ of the acidic aqueous electrolyte plays a crucial part in enhancement the specific capacity, and the abundant pseudocapacitive functional groups on the surface of the NODPC-1.0 sample play the key role in the improvement of electrochemical cycle stability under a broad voltage window.
Designing a carbon material with a unique composition and surface functional groups for offering high specific capacity in a wide voltage window is of great significance to improve the energy density for the supercapacitor in a cheap and eco-friendly aqueous electrolyte. Herein, we develop an efficient strategy to synthesize a N, O co-doped hierarchically porous carbon (NODPC-1.0) with moderate specific surface area and pore volume as well as rich heteroatoms using a deep eutectic solvent (DES) as an activator. It is found that NODPC-1.0 with a large proportion of pseudocapacitive functional groups (pyrrole-N, pyridine-N and carbonyl-quinone) can work stable in an acidic 2 mol/L Li2SO4 (pH 2.5) electrolyte, exhibiting specific capacities of 375 and 186 F/g at the current densities of 1.0 and 100 A/g, respectively. Also, the assembled symmetric capacitor using the NODPC-1.0 as the active material and 2 mol/L acidic Li2SO4 (pH 2.5) as the electrolyte shows an outstanding energy density of 74.4 Wh/kg at a high power density of 1.44 kW/kg under a broad voltage window (2.4 V). Relevant comparative experiments indicate that H+ of the acidic aqueous electrolyte plays a crucial part in enhancement the specific capacity, and the abundant pseudocapacitive functional groups on the surface of the NODPC-1.0 sample play the key role in the improvement of electrochemical cycle stability under a broad voltage window.
2022, 33(8): 3889-3893
doi: 10.1016/j.cclet.2021.11.062
Abstract:
Lithium-ion capacitor (LIC), which combines the advantages of lithium-ion battery (LIB) and electrical double layer capacitor (EDLC), has a rapid development during last decade, however, the poor low temperature performance still limits its application. In this paper, three electrolyte additives including vinylene carbonate (VC), fluoroethylene carbonate (FEC) and 1,3,2-dioxathiolane 2,2-dioxide (DTD) have been utilized and their effects on the rate performance of hard carbon (HC) anode of LIC at various temperatures ranging from 25 ℃ to −40 ℃ have been well evaluated. The cell containing FEC shows the best rate performance at various temperatures and has the charge and discharge capability even at −40 ℃. For HC anode, the charge transfer impedance (RCT) increases exponentially at low temperature, while the equivalent series resistance (Rs) and the impedance of solid electrolyte interface (SEI) increase relatively few. At low temperatures, the effect of FEC may be mainly reflected in its effect on the charge transfer process.
Lithium-ion capacitor (LIC), which combines the advantages of lithium-ion battery (LIB) and electrical double layer capacitor (EDLC), has a rapid development during last decade, however, the poor low temperature performance still limits its application. In this paper, three electrolyte additives including vinylene carbonate (VC), fluoroethylene carbonate (FEC) and 1,3,2-dioxathiolane 2,2-dioxide (DTD) have been utilized and their effects on the rate performance of hard carbon (HC) anode of LIC at various temperatures ranging from 25 ℃ to −40 ℃ have been well evaluated. The cell containing FEC shows the best rate performance at various temperatures and has the charge and discharge capability even at −40 ℃. For HC anode, the charge transfer impedance (RCT) increases exponentially at low temperature, while the equivalent series resistance (Rs) and the impedance of solid electrolyte interface (SEI) increase relatively few. At low temperatures, the effect of FEC may be mainly reflected in its effect on the charge transfer process.
2022, 33(8): 3894-3898
doi: 10.1016/j.cclet.2021.11.073
Abstract:
The lithium dendrite growth is still a serious challenge and impeding the realistic applications of all-solid-state lithium batteries. In view of the amide containing sediment layer can be stable on lithium/cathodes, a composite polymer electrolyte with amide-based matrix is in-situ built on porous electrodes. With the introduction of amide, the polymer electrolyte presents excellent ability to inhibit lithium dendrite growth and makes the Li/Li symmetric battery stably work for 500 h with a good ionic conductivity of 4.25 × 10−5 S/cm at 40 ℃. The solid electrolyte also shows a wide electrochemical stable window and good interface contact with the porous cathode. Utilizing this composite polymer electrolyte, the all-solid-state Li/LiFePO4 battery shows an initial discharge capacity of 146.5 mAh/g at 0.1 C under 40 ℃ and remains 81.4% in 100 cycles. The polymer electrolyte also can present better properties after modification. These results demonstrate that the presented PA-based composite polymer electrolyte could be served as a good electrolyte candidate for all-solid-state lithium-ion batteries.
The lithium dendrite growth is still a serious challenge and impeding the realistic applications of all-solid-state lithium batteries. In view of the amide containing sediment layer can be stable on lithium/cathodes, a composite polymer electrolyte with amide-based matrix is in-situ built on porous electrodes. With the introduction of amide, the polymer electrolyte presents excellent ability to inhibit lithium dendrite growth and makes the Li/Li symmetric battery stably work for 500 h with a good ionic conductivity of 4.25 × 10−5 S/cm at 40 ℃. The solid electrolyte also shows a wide electrochemical stable window and good interface contact with the porous cathode. Utilizing this composite polymer electrolyte, the all-solid-state Li/LiFePO4 battery shows an initial discharge capacity of 146.5 mAh/g at 0.1 C under 40 ℃ and remains 81.4% in 100 cycles. The polymer electrolyte also can present better properties after modification. These results demonstrate that the presented PA-based composite polymer electrolyte could be served as a good electrolyte candidate for all-solid-state lithium-ion batteries.
2022, 33(8): 3899-3902
doi: 10.1016/j.cclet.2021.11.059
Abstract:
Two novel uranium-containing selenotungstates Na3[H19(UO2)2(μ2-O)(Se2W14O52)2]·41H2O (U2) and (NH4)10[H4(SeO)2(UO2)2(H2O)2(H2Se2W14O52)(Se2W14O52)]·66H2O (Se2U2) based on the {Se2W14O52} unit were successfully prepared and fully characterized. To our knowledge, the uranium is firstly introduced into the selenotungstates. Moreover, it is notable that U2 exhibits excellent Lewis acid-base catalytic activities in the condensation cyclization of sulfonyl hydrazides with diketones to synthesize polysubstituted pyrazoles. All the desired products were obtained in moderate to good yields (up to 99%).
Two novel uranium-containing selenotungstates Na3[H19(UO2)2(μ2-O)(Se2W14O52)2]·41H2O (U2) and (NH4)10[H4(SeO)2(UO2)2(H2O)2(H2Se2W14O52)(Se2W14O52)]·66H2O (Se2U2) based on the {Se2W14O52} unit were successfully prepared and fully characterized. To our knowledge, the uranium is firstly introduced into the selenotungstates. Moreover, it is notable that U2 exhibits excellent Lewis acid-base catalytic activities in the condensation cyclization of sulfonyl hydrazides with diketones to synthesize polysubstituted pyrazoles. All the desired products were obtained in moderate to good yields (up to 99%).
2022, 33(8): 3903-3908
doi: 10.1016/j.cclet.2021.11.075
Abstract:
Fe-N-C structures have been considered as a candidate to replace noble metal catalysts towards oxygen reduction reaction (ORR) due to their excellent electrocatalytic activity and durability. Herein, a zinc-mediated synthesis strategy is proposed for N-doped graphitic porous carbon encapsulated uniform dispersed Fe3C nanoparticles coupled with atomically dispersed Fe-Nx moieties (NPC/Fe-N-C) derived from biomass coconut shell. The introduction of zinc species could be conductive to the dispersion of iron species and formation of porous structures. Density functional theory calculations demonstrate that the N-doped carbon coating structures can weaken the oxygen intermediates adsorption energy barrier of Fe3C. Beside, the graphitic carbon could promote the electron transfer during the electrochemical reaction. These special structures enable NPC/Fe-N-C to have excellent ORR activity with an Eonset of 1.0 V, which is much better than Pt/C. Furthermore, the zinc-air battery assembled by pairing NPC/Fe-N-C with a high-efficiency oxygen evolution reaction (OER) catalyst can continuously and stably operate a charge-discharge potential gap of 0.8 V at 10 mA/cm2 for more than 600 h. More importantly, the assembled batteries could drive overall water splitting device, realizing the effective energy conversion.
Fe-N-C structures have been considered as a candidate to replace noble metal catalysts towards oxygen reduction reaction (ORR) due to their excellent electrocatalytic activity and durability. Herein, a zinc-mediated synthesis strategy is proposed for N-doped graphitic porous carbon encapsulated uniform dispersed Fe3C nanoparticles coupled with atomically dispersed Fe-Nx moieties (NPC/Fe-N-C) derived from biomass coconut shell. The introduction of zinc species could be conductive to the dispersion of iron species and formation of porous structures. Density functional theory calculations demonstrate that the N-doped carbon coating structures can weaken the oxygen intermediates adsorption energy barrier of Fe3C. Beside, the graphitic carbon could promote the electron transfer during the electrochemical reaction. These special structures enable NPC/Fe-N-C to have excellent ORR activity with an Eonset of 1.0 V, which is much better than Pt/C. Furthermore, the zinc-air battery assembled by pairing NPC/Fe-N-C with a high-efficiency oxygen evolution reaction (OER) catalyst can continuously and stably operate a charge-discharge potential gap of 0.8 V at 10 mA/cm2 for more than 600 h. More importantly, the assembled batteries could drive overall water splitting device, realizing the effective energy conversion.
2022, 33(8): 3909-3915
doi: 10.1016/j.cclet.2021.11.046
Abstract:
Lithium–sulfur (Li–S) battery is labeled as a promising high-energy-density battery system, but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications. Herein, an integrated approach is proposed to fabricate the high-performance rGO/VS4/S cathode composites through a simple one-step solvothermal method, where nano sulfur and VS4 particles are uniformly distributed on the conductive rGO matrix. rGO and sulfiphilic VS4 provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides (LiPS). Meanwhile, VS4 could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS. Correspondingly, the rGO/VS4/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles, with a capacity retention rate of 82.3%. The capacity fade rate could lower to 0.0374% per cycle at 1 C. Moreover, capacity still sustains 795 mAh/g after 100 cycles in the relatively high-sulfur-loading battery (6.5 mg/cm2). Thus, the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li–S batteries.
Lithium–sulfur (Li–S) battery is labeled as a promising high-energy-density battery system, but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications. Herein, an integrated approach is proposed to fabricate the high-performance rGO/VS4/S cathode composites through a simple one-step solvothermal method, where nano sulfur and VS4 particles are uniformly distributed on the conductive rGO matrix. rGO and sulfiphilic VS4 provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides (LiPS). Meanwhile, VS4 could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS. Correspondingly, the rGO/VS4/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles, with a capacity retention rate of 82.3%. The capacity fade rate could lower to 0.0374% per cycle at 1 C. Moreover, capacity still sustains 795 mAh/g after 100 cycles in the relatively high-sulfur-loading battery (6.5 mg/cm2). Thus, the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li–S batteries.
2022, 33(8): 3916-3920
doi: 10.1016/j.cclet.2021.11.085
Abstract:
The development of efficient and cost-effective oxygen evolution reaction (OER) electrocatalysts is crucial for clean energy conversion and storage devices, such as water-splitting, CO2 reduction, and metal-air batteries. Herein, we report an efficient 2-dimensional OER catalyst of ultrathin nickel-iron sulfide nanosheets (NiFeS-NS). Dodecanethiol is employed in the synthesis, which prohibits the growth along the Z-axis, thus a nanosheet is obtained. The NiFeS-NS shows high OER catalytic activity, which only requires a small overpotential of 273 mV to achieve the OER current density of 10 mA/cm2 in alkaline electrolyte, and almost no decay after 150 h of chronopotentiometry test. The high performance is attributed to the 2-dimensional structure, the synergistic effect from the Ni and Fe components which promotes the formation of the high valence Ni species, and the tuning effect from the in-situ generated sulfate doping. This work demonstrates the advantages of the 2-dimensional sulfides in electrocatalysis.
The development of efficient and cost-effective oxygen evolution reaction (OER) electrocatalysts is crucial for clean energy conversion and storage devices, such as water-splitting, CO2 reduction, and metal-air batteries. Herein, we report an efficient 2-dimensional OER catalyst of ultrathin nickel-iron sulfide nanosheets (NiFeS-NS). Dodecanethiol is employed in the synthesis, which prohibits the growth along the Z-axis, thus a nanosheet is obtained. The NiFeS-NS shows high OER catalytic activity, which only requires a small overpotential of 273 mV to achieve the OER current density of 10 mA/cm2 in alkaline electrolyte, and almost no decay after 150 h of chronopotentiometry test. The high performance is attributed to the 2-dimensional structure, the synergistic effect from the Ni and Fe components which promotes the formation of the high valence Ni species, and the tuning effect from the in-situ generated sulfate doping. This work demonstrates the advantages of the 2-dimensional sulfides in electrocatalysis.
2022, 33(8): 3921-3924
doi: 10.1016/j.cclet.2021.11.052
Abstract:
Quasi-two-dimensional (q2D) conducting polymer thin film synergizes the advantageous features of long-range molecular ordering and high intrinsic conductivity, which are promising for flexible thin film-based micro-supercapacitors (MSCs). Herein, we present the high-performance flexible MSCs based on highly ordered quasi-two-dimensional polyaniline (q2D-PANI) thin film using surfactant monolayer assisted interfacial synthesis (SMAIS). Owing to high electrical conductivity, rich redox chemistry, and thin-film morphology, the q2D-PANI MSCs show high volumetric specific capacitance (ca. 360 F/cm3) and energy density (17.9 mWh/cm3), which outperform the state-of-art PANI thin-film based MSCs and promise for future flexible electronics.
Quasi-two-dimensional (q2D) conducting polymer thin film synergizes the advantageous features of long-range molecular ordering and high intrinsic conductivity, which are promising for flexible thin film-based micro-supercapacitors (MSCs). Herein, we present the high-performance flexible MSCs based on highly ordered quasi-two-dimensional polyaniline (q2D-PANI) thin film using surfactant monolayer assisted interfacial synthesis (SMAIS). Owing to high electrical conductivity, rich redox chemistry, and thin-film morphology, the q2D-PANI MSCs show high volumetric specific capacitance (ca. 360 F/cm3) and energy density (17.9 mWh/cm3), which outperform the state-of-art PANI thin-film based MSCs and promise for future flexible electronics.
2022, 33(8): 3925-3930
doi: 10.1016/j.cclet.2021.11.021
Abstract:
Due to its high theoretical capacity and appropriate potential platform, tin-based alloy materials are expected to be a competitive candidate for the next-generation high performance anodes of lithium-ion batteries. Nevertheless, the immense volume change during the lithium-ion insert process leads to severe disadvantages of structural damage and capacity fade, which limits its practical application. In this work, a three-dimensional (3D) multicore-shell hollow nanobox encapsulated by carbon layer is obtained via a three-step method of hydrothermal reaction, annealing and alkali etching. During the electrochemical reactions, the CoSn@void@C nanoboxes provide internal space to compensate the volumetric change upon the lithiation of Sn, while the inactive component of Co acts as chemical buffers to withstand the anisotropic expansion of nanoparticles. Owing to the above-mentioned advantages, the elaborated anode delivers an excellent capacity of 788.2 mAh/g at 100 mA/g after 100 cycles and considerable capacity retention of 519.2 mAh/g even at a high current density of 1 A/g after 300 cycles. The superior stability and high performance indicate its capability as promising anodes for lithium-ion batteries.
Due to its high theoretical capacity and appropriate potential platform, tin-based alloy materials are expected to be a competitive candidate for the next-generation high performance anodes of lithium-ion batteries. Nevertheless, the immense volume change during the lithium-ion insert process leads to severe disadvantages of structural damage and capacity fade, which limits its practical application. In this work, a three-dimensional (3D) multicore-shell hollow nanobox encapsulated by carbon layer is obtained via a three-step method of hydrothermal reaction, annealing and alkali etching. During the electrochemical reactions, the CoSn@void@C nanoboxes provide internal space to compensate the volumetric change upon the lithiation of Sn, while the inactive component of Co acts as chemical buffers to withstand the anisotropic expansion of nanoparticles. Owing to the above-mentioned advantages, the elaborated anode delivers an excellent capacity of 788.2 mAh/g at 100 mA/g after 100 cycles and considerable capacity retention of 519.2 mAh/g even at a high current density of 1 A/g after 300 cycles. The superior stability and high performance indicate its capability as promising anodes for lithium-ion batteries.
2022, 33(8): 3931-3935
doi: 10.1016/j.cclet.2021.12.014
Abstract:
Iron fluoride (FeF3) is considered as a promising cathode material for Li-ion batteries (LIBs) due to its high theoretical capacity (712 mAh/g) with a 3e− transfer. Herein, we have designed a strategy of hierarchical and mesoporous FeF3/rGO hybrids for LIBs, where the hollow FeF3 nanospheres are the main contributor to the specific capacity and the 2D rGO nanosheets are the matrix elevating the electronic conductivity and buffering the volume expansion. The unique FeF3/rGO hybrid can be rationally synthesized by a non-aqueous in-situ precipitation method, offering the merits of large specific surface area with rich active sites, fast transport channels for lithium ions, effective alleviation of volume expansion during cycles, and accelerating the electrochemical reaction kinetics. The FeF3/rGO hybrid electrode possesses a high initial discharge capacity of 553.9 mAh/g at a rate of 0.5 C with 378 mAh/g after 100 cycles, acceptable rate capability with 168 mAh/g at 2 C, and feasible high-temperature operation (320 mAh/g at 70 ℃). The superior electrochemical behaviors presented here demonstrates that the FeF3/rGO hybrid is a potential electrode for LIBs, which may open up a new vision to design high-efficiency energy-storage devices such as LIBs based on transition metal fluorides.
Iron fluoride (FeF3) is considered as a promising cathode material for Li-ion batteries (LIBs) due to its high theoretical capacity (712 mAh/g) with a 3e− transfer. Herein, we have designed a strategy of hierarchical and mesoporous FeF3/rGO hybrids for LIBs, where the hollow FeF3 nanospheres are the main contributor to the specific capacity and the 2D rGO nanosheets are the matrix elevating the electronic conductivity and buffering the volume expansion. The unique FeF3/rGO hybrid can be rationally synthesized by a non-aqueous in-situ precipitation method, offering the merits of large specific surface area with rich active sites, fast transport channels for lithium ions, effective alleviation of volume expansion during cycles, and accelerating the electrochemical reaction kinetics. The FeF3/rGO hybrid electrode possesses a high initial discharge capacity of 553.9 mAh/g at a rate of 0.5 C with 378 mAh/g after 100 cycles, acceptable rate capability with 168 mAh/g at 2 C, and feasible high-temperature operation (320 mAh/g at 70 ℃). The superior electrochemical behaviors presented here demonstrates that the FeF3/rGO hybrid is a potential electrode for LIBs, which may open up a new vision to design high-efficiency energy-storage devices such as LIBs based on transition metal fluorides.
2022, 33(8): 3936-3940
doi: 10.1016/j.cclet.2021.11.015
Abstract:
Aqueous zinc energy storage devices, holding various merits such as high specific capacity and low costs, have attracted extensive attention in recent years. Nevertheless, Zn metal anodes still suffer from a short lifespan and low Coulombic efficiency due to corrosion and side reactions in aqueous electrolytes. In this paper, we construct an artificial Sn inorganic layer on Zn metal anode through a facile strategy of atom exchange. The Sn layer suppresses Zn dendrite growth by facilitating homogeneous Zn plating and stripping during charge and discharge processes. Meanwhile, the Sn protective layer also serves as a physical barrier to decrease Zn corrosion and hydrogen generation. As a result, The Sn-coated anode (Sn|Zn) exhibits a low polarization voltage (~34 mV at 0.5 mAh/cm2) after 800 testing hours and displays a smooth and an even surface without corrosion. Moreover, the zinc ion capacitor (Sn|Zn||activated carbon) is assembled with an enhanced capacity of 42 mAh/g and a capacity retention of 95% after 10,000 cycles at 5 A/g. This work demonstrates a feasible approach for the commercialization of aqueous Zn-based energy storage devices.
Aqueous zinc energy storage devices, holding various merits such as high specific capacity and low costs, have attracted extensive attention in recent years. Nevertheless, Zn metal anodes still suffer from a short lifespan and low Coulombic efficiency due to corrosion and side reactions in aqueous electrolytes. In this paper, we construct an artificial Sn inorganic layer on Zn metal anode through a facile strategy of atom exchange. The Sn layer suppresses Zn dendrite growth by facilitating homogeneous Zn plating and stripping during charge and discharge processes. Meanwhile, the Sn protective layer also serves as a physical barrier to decrease Zn corrosion and hydrogen generation. As a result, The Sn-coated anode (Sn|Zn) exhibits a low polarization voltage (~34 mV at 0.5 mAh/cm2) after 800 testing hours and displays a smooth and an even surface without corrosion. Moreover, the zinc ion capacitor (Sn|Zn||activated carbon) is assembled with an enhanced capacity of 42 mAh/g and a capacity retention of 95% after 10,000 cycles at 5 A/g. This work demonstrates a feasible approach for the commercialization of aqueous Zn-based energy storage devices.
2022, 33(8): 3941-3946
doi: 10.1016/j.cclet.2021.11.027
Abstract:
Two-dimensional (2D) materials with honeycomb, kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects. In order to improve structural diversity of 2D materials to achieve unique properties, here we propose a new quasi-2D honeycomb-star-honeycomb (HSH) lattice based on first-principles calculations. A carbon allotrope named HSH-C10 is designed with the HSH lattice, and its mechanical properties have been intensively investigated through total energy, phonon dispersion, ab initio molecular dynamic simulations, as well as elastic constants calculations. Besides the classical covalent bonds, there is an interesting charge-shift bond in this material from the chemical bonding analysis. Additionally, through the analysis of electronic structure, HSH-C10 is predicted to be a semiconductor with a direct band gap of 2.89 eV, which could combine the desirable characteristics of honeycomb and star lattice. Importantly, by modulating coupling strength, a flat band near the Fermi level can be obtained in compounds HSH-C6Si4 and HSH-C6Ge4, which have potential applications in superconductivity. Insight into such mixed lattice would inspire new materials with properties we have yet to imagine.
Two-dimensional (2D) materials with honeycomb, kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects. In order to improve structural diversity of 2D materials to achieve unique properties, here we propose a new quasi-2D honeycomb-star-honeycomb (HSH) lattice based on first-principles calculations. A carbon allotrope named HSH-C10 is designed with the HSH lattice, and its mechanical properties have been intensively investigated through total energy, phonon dispersion, ab initio molecular dynamic simulations, as well as elastic constants calculations. Besides the classical covalent bonds, there is an interesting charge-shift bond in this material from the chemical bonding analysis. Additionally, through the analysis of electronic structure, HSH-C10 is predicted to be a semiconductor with a direct band gap of 2.89 eV, which could combine the desirable characteristics of honeycomb and star lattice. Importantly, by modulating coupling strength, a flat band near the Fermi level can be obtained in compounds HSH-C6Si4 and HSH-C6Ge4, which have potential applications in superconductivity. Insight into such mixed lattice would inspire new materials with properties we have yet to imagine.
2022, 33(8): 3947-3950
doi: 10.1016/j.cclet.2021.11.026
Abstract:
The first-principles calculations demonstrate that covalently bonded (cb) heterojunction and van der Waals (vdW) heterojunction can coexist in silicene/CeO2 heterojunctions, due to the different stacking patterns. Especially, the cb heterojunction with band gap of 1.97 eV, forms a type-II heterojunction, exhibits good redox performance and has high-effective optical absorption spectra, thus it is a promising photocatalyst for overall water splitting. Besides, for the vdW heterojunction, the Dirac cone of silicene is well kept on CeO2 semiconducting substrate, with a considerable energy gap of 0.43 eV, which can be an ideal material in building silicene-based electronic device. These results may open a new gateway in both of nanoelectronic device and energy conversion for silicene/CeO2 nanocomposites.
The first-principles calculations demonstrate that covalently bonded (cb) heterojunction and van der Waals (vdW) heterojunction can coexist in silicene/CeO2 heterojunctions, due to the different stacking patterns. Especially, the cb heterojunction with band gap of 1.97 eV, forms a type-II heterojunction, exhibits good redox performance and has high-effective optical absorption spectra, thus it is a promising photocatalyst for overall water splitting. Besides, for the vdW heterojunction, the Dirac cone of silicene is well kept on CeO2 semiconducting substrate, with a considerable energy gap of 0.43 eV, which can be an ideal material in building silicene-based electronic device. These results may open a new gateway in both of nanoelectronic device and energy conversion for silicene/CeO2 nanocomposites.
2022, 33(8): 3951-3954
doi: 10.1016/j.cclet.2021.11.024
Abstract:
The uncontrolled growth of lithium dendrites and accumulation of "dead lithium" upon cycling are among the main obstacles that hinder the widespread application of lithium metal anodes. Herein, an ionic liquid (IL) consisting of 1-methyl-1-propylpiperidinium cation (Pp13+) and bis(fluorosulfonyl)imide anion (FSI−), was chosen as the additive in propylene carbonate (PC)-based liquid electrolytes to circumvent the shortcoming of lithium metal anodes. The optimal 1% Pp13FSI acts as the role of electrostatic shielding, lithiophobic effect and participating in the formation of solid electrolyte interface (SEI) layer with enhanced properties. The in-situ optical microscopy records that the addition of IL can effectively inhibit the growth of lithium dendrites and the corrosion of lithium anode. This study delivers an effective modification to optimize electrolytes for stable lithium metal batteries.
The uncontrolled growth of lithium dendrites and accumulation of "dead lithium" upon cycling are among the main obstacles that hinder the widespread application of lithium metal anodes. Herein, an ionic liquid (IL) consisting of 1-methyl-1-propylpiperidinium cation (Pp13+) and bis(fluorosulfonyl)imide anion (FSI−), was chosen as the additive in propylene carbonate (PC)-based liquid electrolytes to circumvent the shortcoming of lithium metal anodes. The optimal 1% Pp13FSI acts as the role of electrostatic shielding, lithiophobic effect and participating in the formation of solid electrolyte interface (SEI) layer with enhanced properties. The in-situ optical microscopy records that the addition of IL can effectively inhibit the growth of lithium dendrites and the corrosion of lithium anode. This study delivers an effective modification to optimize electrolytes for stable lithium metal batteries.
2022, 33(8): 3955-3960
doi: 10.1016/j.cclet.2021.11.094
Abstract:
Rechargeable aqueous zinc-ion batteries are recently gaining incremental attention because of low cost and material abundance, but their development is plagued by limited choices of cathode materials with satisfactory cycling performance. The polyoxometalates perform formidable redox stability and able to participate in multi-electron transfer, which was well-suited for energy storage. Herein, a bi-component polyoxometalate-derivative KNiVO (K2[Ni(H2O)6]2[V10O28]·4H2O polyoxometalates after annealing) is firstly demonstrated as a cathode material for aqueous ZIBs. The layered KV3O8 (KVO) In the bi-component material constitutes Zn2+ migration and storage channels (K+ were substantially replaced by Zn2+ in the activation phase), and the three-dimensional NiV3O8 (NiVO) part acts as skeleton to stabilize the ion channels, which assist the cell to demonstrate a high-rate capacity and specific energy of 229.4 mAh/g and satisfactory cyclability (capacity retention of 99.1% after 4500 cycles at a current density of 4 A/g). These results prove the feasibility of POM as cathode materials precursor and put forward a novel pattern of the Zn2+ storage mechanism in the activated-KNiVO clusters, which also provide a new route for selecting or designing high-performance cathode for aqueous ZIBs and other advanced battery systems.
Rechargeable aqueous zinc-ion batteries are recently gaining incremental attention because of low cost and material abundance, but their development is plagued by limited choices of cathode materials with satisfactory cycling performance. The polyoxometalates perform formidable redox stability and able to participate in multi-electron transfer, which was well-suited for energy storage. Herein, a bi-component polyoxometalate-derivative KNiVO (K2[Ni(H2O)6]2[V10O28]·4H2O polyoxometalates after annealing) is firstly demonstrated as a cathode material for aqueous ZIBs. The layered KV3O8 (KVO) In the bi-component material constitutes Zn2+ migration and storage channels (K+ were substantially replaced by Zn2+ in the activation phase), and the three-dimensional NiV3O8 (NiVO) part acts as skeleton to stabilize the ion channels, which assist the cell to demonstrate a high-rate capacity and specific energy of 229.4 mAh/g and satisfactory cyclability (capacity retention of 99.1% after 4500 cycles at a current density of 4 A/g). These results prove the feasibility of POM as cathode materials precursor and put forward a novel pattern of the Zn2+ storage mechanism in the activated-KNiVO clusters, which also provide a new route for selecting or designing high-performance cathode for aqueous ZIBs and other advanced battery systems.
2022, 33(8): 3961-3967
doi: 10.1016/j.cclet.2022.03.037
Abstract:
Hierarchical porous carbon (HPC) from bituminous coal was designed and synthesized through pyrolysis foaming and KOH activation. The obtained HPC (NCF-KOH) were characterized by a high specific surface area (SBET) of 3472.41 m2/g, appropriate mesopores with Vmes/Vtotal of 57%, and a proper amount of surface oxygen content (10.03%). This NCF-KOH exhibited a high specific capacitance of 487 F/g at 1.0 A/g and a rate capability of 400 F/g at 50 A/g based on the three-electrode configuration. As an electrode for a symmetric capacitor, a specific capacitance of 299 F/g at 0.5 A/g was exhibited, and the specific capacitance retained 96% of the initial capacity at 5 A/g after 10,000 cycles. Furthermore, under the power density of 249.6 W/kg in 6 mol/L KOH, a high energy density of 10.34 Wh/kg was obtained. The excellent charge storage capability benefited from its interconnected hierarchical pore structure with high accessible surface area and the suitable amount of oxygen-containing functional groups. Thus, an effective strategy to synthesize HPC for high-performance supercapacitors serves as a promising way of converting coal into advanced carbon materials.
Hierarchical porous carbon (HPC) from bituminous coal was designed and synthesized through pyrolysis foaming and KOH activation. The obtained HPC (NCF-KOH) were characterized by a high specific surface area (SBET) of 3472.41 m2/g, appropriate mesopores with Vmes/Vtotal of 57%, and a proper amount of surface oxygen content (10.03%). This NCF-KOH exhibited a high specific capacitance of 487 F/g at 1.0 A/g and a rate capability of 400 F/g at 50 A/g based on the three-electrode configuration. As an electrode for a symmetric capacitor, a specific capacitance of 299 F/g at 0.5 A/g was exhibited, and the specific capacitance retained 96% of the initial capacity at 5 A/g after 10,000 cycles. Furthermore, under the power density of 249.6 W/kg in 6 mol/L KOH, a high energy density of 10.34 Wh/kg was obtained. The excellent charge storage capability benefited from its interconnected hierarchical pore structure with high accessible surface area and the suitable amount of oxygen-containing functional groups. Thus, an effective strategy to synthesize HPC for high-performance supercapacitors serves as a promising way of converting coal into advanced carbon materials.
2022, 33(8): 3968-3972
doi: 10.1016/j.cclet.2021.11.006
Abstract:
Surfactants with polyoxometalates (POMs) as polar head groups have shown fascinating self-assembly behaviors and various functional applications. However, self-assembly them into reverse micelles is still challenging owing to the large molecular size and intermolecular strong electrostatic repulsions of POM heads. In this work, a zwitterionic POM-based surfactant was synthesized by covalently grafting two cationic long alkyl tails onto the lacunary site of [PW11O39]7−. With decreased electrostatic repulsions and increased hydrophobic effect, the POM-based reverse micelles with an average diameter of 5 nm were obtained. Interestingly, when these reverse micelles were applied for catalyzing the oxidation of styrene, an unprecedented β-hydroxyl peroxide compound of 2-hydroxyl-2-phenylethan-1-tert-butylperoxide was produced in high selectivity of 95.2%. In comparison, the cetyltrimethylammonium electrostatically encapsulated POMs mainly generated the epoxides or 1, 2-diols. A free radical mechanism was proposed for the oxidation reaction catalyzed by the zwitterionic POM surfactants.
Surfactants with polyoxometalates (POMs) as polar head groups have shown fascinating self-assembly behaviors and various functional applications. However, self-assembly them into reverse micelles is still challenging owing to the large molecular size and intermolecular strong electrostatic repulsions of POM heads. In this work, a zwitterionic POM-based surfactant was synthesized by covalently grafting two cationic long alkyl tails onto the lacunary site of [PW11O39]7−. With decreased electrostatic repulsions and increased hydrophobic effect, the POM-based reverse micelles with an average diameter of 5 nm were obtained. Interestingly, when these reverse micelles were applied for catalyzing the oxidation of styrene, an unprecedented β-hydroxyl peroxide compound of 2-hydroxyl-2-phenylethan-1-tert-butylperoxide was produced in high selectivity of 95.2%. In comparison, the cetyltrimethylammonium electrostatically encapsulated POMs mainly generated the epoxides or 1, 2-diols. A free radical mechanism was proposed for the oxidation reaction catalyzed by the zwitterionic POM surfactants.
2022, 33(8): 3973-3976
doi: 10.1016/j.cclet.2021.11.016
Abstract:
Amphiphilic molecules adsorbed at the interface could control the orientation of liquid crystals (LCs) while LCs in turn could influence the distributions of amphiphilic molecules. The studies on the interactions between liquid crystals and amphiphilic molecules at the interface are important for the development of molecular sensors. In this paper, we demonstrate that the development of smectic LC ordering from isotropic at the LC/water interface could induce local high-density distributions of amphiphilic phospholipids. Mixtures of liquid crystals and phospholipids in chloroform are first emulsified in water. By fluorescently labeling the phospholipids adsorbed at the interface, their distributions are visualized under fluorescent confocal microscope. Interestingly, local high-density distributions of phospholipids showing a high fluorescent intensity are observed on the surface of LC droplets. Investigations on the correlation between phospholipid density, surface tension and smectic LC ordering suggest that when domains of smectic LC layers nucleate and grow from isotropic at the LC/water interface as chloroform slowly evaporates at room temperature, phospholipids transition from liquid-expanded to liquid-condensed phases in response to the smectic ordering, which induces a higher surface tension at the interface. The results will provide an important insight into the interactions between liquid crystals and amphiphilic molecules at the interface.
Amphiphilic molecules adsorbed at the interface could control the orientation of liquid crystals (LCs) while LCs in turn could influence the distributions of amphiphilic molecules. The studies on the interactions between liquid crystals and amphiphilic molecules at the interface are important for the development of molecular sensors. In this paper, we demonstrate that the development of smectic LC ordering from isotropic at the LC/water interface could induce local high-density distributions of amphiphilic phospholipids. Mixtures of liquid crystals and phospholipids in chloroform are first emulsified in water. By fluorescently labeling the phospholipids adsorbed at the interface, their distributions are visualized under fluorescent confocal microscope. Interestingly, local high-density distributions of phospholipids showing a high fluorescent intensity are observed on the surface of LC droplets. Investigations on the correlation between phospholipid density, surface tension and smectic LC ordering suggest that when domains of smectic LC layers nucleate and grow from isotropic at the LC/water interface as chloroform slowly evaporates at room temperature, phospholipids transition from liquid-expanded to liquid-condensed phases in response to the smectic ordering, which induces a higher surface tension at the interface. The results will provide an important insight into the interactions between liquid crystals and amphiphilic molecules at the interface.
2022, 33(8): 3977-3980
doi: 10.1016/j.cclet.2021.11.003
Abstract:
Organic room temperature phosphorescent (ORTP) materials provide an exciting research direction for phosphorescent oxygen (O2) sensors due to their high sensitivity and rapid response to O2. However, most pure ORTP materials are tightly-packed aromatic compound crystals in a face-to-face manner, which largely prohibits effective O2 diffusion for sensing. Thus, how to solve this contradiction still faces huge challenges. Here, the use of organic phosphorescent indicator carbon dots (CDs), inorganic matrix layered double hydroxides (LDHs) and polymers (PVA) successfully prepared an ultra-long RTP composite film whose phosphorescence decay intensity is linearly related to O2 concentration. More importantly, the use of the abundant O2 defects (Vo) on the surface of the inorganic matrix LDHs to adsorb O2, which further accelerates the phosphorescence quenching of the thin film and improves the O2 response. This strategy will provide the possibility to develop high-sensitivity phosphorescent O2 sensors from a new perspective.
Organic room temperature phosphorescent (ORTP) materials provide an exciting research direction for phosphorescent oxygen (O2) sensors due to their high sensitivity and rapid response to O2. However, most pure ORTP materials are tightly-packed aromatic compound crystals in a face-to-face manner, which largely prohibits effective O2 diffusion for sensing. Thus, how to solve this contradiction still faces huge challenges. Here, the use of organic phosphorescent indicator carbon dots (CDs), inorganic matrix layered double hydroxides (LDHs) and polymers (PVA) successfully prepared an ultra-long RTP composite film whose phosphorescence decay intensity is linearly related to O2 concentration. More importantly, the use of the abundant O2 defects (Vo) on the surface of the inorganic matrix LDHs to adsorb O2, which further accelerates the phosphorescence quenching of the thin film and improves the O2 response. This strategy will provide the possibility to develop high-sensitivity phosphorescent O2 sensors from a new perspective.
2022, 33(8): 3981-3986
doi: 10.1016/j.cclet.2021.11.032
Abstract:
It is of great importance to directionally construct advanced carbon host to achieve high-performance carbon/sulfur cathodes for lithium sulfur batteries (LSBs). Herein, we report a unique hollow pumpkin-like carbon with notable rich-wrinkle microstructure and intrinsically dual doping with N & P elements via a facile annealing process of Aspergillus niger spore. Furthermore, highly conductive polar absorbents, TiC nanoparticles, are in situ implanted into the above Aspergillus niger spore carbon (ANSC) by carbothermal reaction, accordingly forming high-performance ANSC/TiC composite host for sulfur. Impressively, TiC nanoparticles play dual roles of not only pore formation in ANSC matrix but also enhancement of chemical absorption with polysulfides. With the positive synergistic effect between N & P co-doped ANSC matrix and TiC polar absorbent, the designed ANSC/TiC-S cathodes show unique advantages including larger accommodation space for sulfur, higher surface area, enhanced conductivity and better chemical absorption with soluble polysulfide intermediates. Consequently, the ANSC/TiC-S cathodes are endowed with good rate performance (496 mAh/g at 0.5 C) and enhanced long-term cycling stability (736 mAh/g with a capacity retention of 78.8% at 0.1 C after 100 cycles). Our research opens a new door to controllably design advanced composite cathodes from microorganisms for application in lithium sulfur batteries.
It is of great importance to directionally construct advanced carbon host to achieve high-performance carbon/sulfur cathodes for lithium sulfur batteries (LSBs). Herein, we report a unique hollow pumpkin-like carbon with notable rich-wrinkle microstructure and intrinsically dual doping with N & P elements via a facile annealing process of Aspergillus niger spore. Furthermore, highly conductive polar absorbents, TiC nanoparticles, are in situ implanted into the above Aspergillus niger spore carbon (ANSC) by carbothermal reaction, accordingly forming high-performance ANSC/TiC composite host for sulfur. Impressively, TiC nanoparticles play dual roles of not only pore formation in ANSC matrix but also enhancement of chemical absorption with polysulfides. With the positive synergistic effect between N & P co-doped ANSC matrix and TiC polar absorbent, the designed ANSC/TiC-S cathodes show unique advantages including larger accommodation space for sulfur, higher surface area, enhanced conductivity and better chemical absorption with soluble polysulfide intermediates. Consequently, the ANSC/TiC-S cathodes are endowed with good rate performance (496 mAh/g at 0.5 C) and enhanced long-term cycling stability (736 mAh/g with a capacity retention of 78.8% at 0.1 C after 100 cycles). Our research opens a new door to controllably design advanced composite cathodes from microorganisms for application in lithium sulfur batteries.
2022, 33(8): 3987-3992
doi: 10.1016/j.cclet.2021.11.034
Abstract:
Green hydrogen production and CO2 fixation have been identified as the fundamental techniques for sustainable economy. The open challenge is to develop high performance catalysts for hydrogen evolution reaction (HER) and CO2 electroreduction (CO2ER) to valuable chemicals. Under such context, this work reported computational efforts to design promising electrocatalyst for HER and CO2ER based on the swarm-intelligence algorithm. Among the family of transition-metal phosphides (TMPs), Pt2P3 monolayer has been identified as excellent bifunctional catalysts due to high stability, excellent conductivity and superior catalytic performance. Different from typical d-block catalysts, p-band center presented by P atoms within Pt2P3 monolayer plays the essential role for its reactivity towards HER and CO2ER, underlining the key value of p-electrons in advanced catalyst design and thus providing a promising strategy to further develop novel catalysts made of p-block elements for various energy applications.
Green hydrogen production and CO2 fixation have been identified as the fundamental techniques for sustainable economy. The open challenge is to develop high performance catalysts for hydrogen evolution reaction (HER) and CO2 electroreduction (CO2ER) to valuable chemicals. Under such context, this work reported computational efforts to design promising electrocatalyst for HER and CO2ER based on the swarm-intelligence algorithm. Among the family of transition-metal phosphides (TMPs), Pt2P3 monolayer has been identified as excellent bifunctional catalysts due to high stability, excellent conductivity and superior catalytic performance. Different from typical d-block catalysts, p-band center presented by P atoms within Pt2P3 monolayer plays the essential role for its reactivity towards HER and CO2ER, underlining the key value of p-electrons in advanced catalyst design and thus providing a promising strategy to further develop novel catalysts made of p-block elements for various energy applications.
2022, 33(8): 3993-3998
doi: 10.1016/j.cclet.2021.11.035
Abstract:
The unveiling of MOF growth mechanism is hampered by the lack of fundamental knowledge about the very early stage of nucleation, especially the form and ratio of molecular species in the solution for crystal growth. Herein, we report the detection of growth species for a series of MOFs with mono-linker, Cu-MOF-2-BDC and Cu-MOF-2-NDC, and two linkers, MTV-MOF-2-(C4H4), by high resolution ESI-MS, where a large variety of Cu-containing species are identified unambiguously. The solvent molecules such as H2O, methanol and DMF participate in the formation of these species, other than ethanol. Furthermore, in the growth solution of MTV-MOF-2-(C4H4), growth species containing two different organic linkers are observed. The feeding ratio is not the only factor controlling the distribution of growth species for MTV-MOFs, but also the solvent involves in coordination, an aspect usually overlooked previously.
The unveiling of MOF growth mechanism is hampered by the lack of fundamental knowledge about the very early stage of nucleation, especially the form and ratio of molecular species in the solution for crystal growth. Herein, we report the detection of growth species for a series of MOFs with mono-linker, Cu-MOF-2-BDC and Cu-MOF-2-NDC, and two linkers, MTV-MOF-2-(C4H4), by high resolution ESI-MS, where a large variety of Cu-containing species are identified unambiguously. The solvent molecules such as H2O, methanol and DMF participate in the formation of these species, other than ethanol. Furthermore, in the growth solution of MTV-MOF-2-(C4H4), growth species containing two different organic linkers are observed. The feeding ratio is not the only factor controlling the distribution of growth species for MTV-MOFs, but also the solvent involves in coordination, an aspect usually overlooked previously.
2022, 33(8): 3999-4002
doi: 10.1016/j.cclet.2021.11.055
Abstract:
Constructing molecule@support composites is an attractive strategy to realize heterogeneous molecular electrocatalysis. Herein, we synthesized metal-organic framework (MOF)-supported molecular catalysts for hydrogen evolution and oxygen reduction reaction (HER/ORR). Ligand exchange strategy was used to prepare molecule@support hybrids due to the same functional group. A series of hybrids were obtained using Co porphyrin (1) and different MOFs including MIL-88(Fe), MOF-5(NiCo) and UIO-66(Zr). The 1@MOF-5(NiCo) had the best HER and ORR activity compared with 1@MIL-88(Fe) and 1@MOF-5(NiCo). These hybrids also exhibited tunable selectivity for ORR with four-electron process, which can be attributed to the synergistic effect of porphyrin molecules and MOFs. This work provides a possibility for molecular catalysts to improve activity of HER and tune selectivity of ORR.
Constructing molecule@support composites is an attractive strategy to realize heterogeneous molecular electrocatalysis. Herein, we synthesized metal-organic framework (MOF)-supported molecular catalysts for hydrogen evolution and oxygen reduction reaction (HER/ORR). Ligand exchange strategy was used to prepare molecule@support hybrids due to the same functional group. A series of hybrids were obtained using Co porphyrin (1) and different MOFs including MIL-88(Fe), MOF-5(NiCo) and UIO-66(Zr). The 1@MOF-5(NiCo) had the best HER and ORR activity compared with 1@MIL-88(Fe) and 1@MOF-5(NiCo). These hybrids also exhibited tunable selectivity for ORR with four-electron process, which can be attributed to the synergistic effect of porphyrin molecules and MOFs. This work provides a possibility for molecular catalysts to improve activity of HER and tune selectivity of ORR.
2022, 33(8): 4003-4007
doi: 10.1016/j.cclet.2021.11.088
Abstract:
Developing efficient and inexpensive OER electrocatalysts is a challenge for overall water splitting. Herein, the heterostructured FeCo LDH@NiCoP/NF nanowire arrays with high performance were rationally designed and prepared using an interface engineering strategy. Benefitting from the special heterostructure between FeCo LDH and NiCoP, the as-synthesized FeCo LDH@NiCoP/NF electrocatalyst exhibits outstanding OER performance with an exceptionally low overpotential of 206 mV to achieve 20 mA/cm2 current density in an alkaline electrolyte. Importantly, a cell constructed using the FeCo LDH@NiCoP/NF electrocatalyst as cathode and anode just needs a voltage of 1.48 V at 10 mA/cm2, and shows excellent stability over 80 h. Experimental and theoretical results verified that the introduction of NiCoP efficiently regulates the electronic structure of FeCo LDH, which tremendously boosts the conductivity and intrinsic catalytic activity of FeCo LDH@NiCoP/NF electrocatalyst. The present work provides guidance for the preparation of other efficient and cheap electrocatalytic materials.
Developing efficient and inexpensive OER electrocatalysts is a challenge for overall water splitting. Herein, the heterostructured FeCo LDH@NiCoP/NF nanowire arrays with high performance were rationally designed and prepared using an interface engineering strategy. Benefitting from the special heterostructure between FeCo LDH and NiCoP, the as-synthesized FeCo LDH@NiCoP/NF electrocatalyst exhibits outstanding OER performance with an exceptionally low overpotential of 206 mV to achieve 20 mA/cm2 current density in an alkaline electrolyte. Importantly, a cell constructed using the FeCo LDH@NiCoP/NF electrocatalyst as cathode and anode just needs a voltage of 1.48 V at 10 mA/cm2, and shows excellent stability over 80 h. Experimental and theoretical results verified that the introduction of NiCoP efficiently regulates the electronic structure of FeCo LDH, which tremendously boosts the conductivity and intrinsic catalytic activity of FeCo LDH@NiCoP/NF electrocatalyst. The present work provides guidance for the preparation of other efficient and cheap electrocatalytic materials.
2022, 33(8): 4008-4012
doi: 10.1016/j.cclet.2021.11.086
Abstract:
The large overpotential for conventional Li-O2 batteries is an enormous challenge, which impedes their practical application. Here, we prepare a defective TiO2 (Ov-TiO2) hollow nanosphere as photo-electrocatalyst for photo-assisted Li-O2 batteries to reduce the overpotential. Under illumination, the oxygen vacancies as a charge separation center contribute to the separation of electrons and holes. The generated electrons could promote reducing O2 to Li2O2 during oxygen reduction reaction (ORR) process, while the generated holes are beneficial to Li2O2 decomposition during oxygen evolution reaction (OER) process. Additionally, the proper concentration of oxygen vacancies will decrease the recombination rate between electrons and holes. The photo-assisted Li-O2 batteries with Ov-TiO2-650 exhibit advanced performances, such as the low overpotential (0.70 V), the fine rate capability, and the considerable reversibility accompanied with the formation/decomposition of Li2O2. We expect that these results could open a new mind to design of highly efficient photo-electrocatalysts for photo-assisted Li-O2 battery.
The large overpotential for conventional Li-O2 batteries is an enormous challenge, which impedes their practical application. Here, we prepare a defective TiO2 (Ov-TiO2) hollow nanosphere as photo-electrocatalyst for photo-assisted Li-O2 batteries to reduce the overpotential. Under illumination, the oxygen vacancies as a charge separation center contribute to the separation of electrons and holes. The generated electrons could promote reducing O2 to Li2O2 during oxygen reduction reaction (ORR) process, while the generated holes are beneficial to Li2O2 decomposition during oxygen evolution reaction (OER) process. Additionally, the proper concentration of oxygen vacancies will decrease the recombination rate between electrons and holes. The photo-assisted Li-O2 batteries with Ov-TiO2-650 exhibit advanced performances, such as the low overpotential (0.70 V), the fine rate capability, and the considerable reversibility accompanied with the formation/decomposition of Li2O2. We expect that these results could open a new mind to design of highly efficient photo-electrocatalysts for photo-assisted Li-O2 battery.
2022, 33(8): 4013-4016
doi: 10.1016/j.cclet.2021.12.007
Abstract:
A novel type sandwich-like composite films composed of ZIF-8 and CdTe QDs were successfully constructed through facile layer-by-layer assembly strategy and their potential applications were also explored. Based on the limitation effects of the aperture of ZIF-8, CdTe QDs/ZIF-8 fluorescent composite films exhibit obvious selective optical response toward hydrogen peroxide and folic acid. Furthermore, tunable colorful light emission composite films in the red-green region are obtained through incorporating two different sized QDs and ZIF-8 films into one composite films.
A novel type sandwich-like composite films composed of ZIF-8 and CdTe QDs were successfully constructed through facile layer-by-layer assembly strategy and their potential applications were also explored. Based on the limitation effects of the aperture of ZIF-8, CdTe QDs/ZIF-8 fluorescent composite films exhibit obvious selective optical response toward hydrogen peroxide and folic acid. Furthermore, tunable colorful light emission composite films in the red-green region are obtained through incorporating two different sized QDs and ZIF-8 films into one composite films.
2022, 33(8): 4017-4020
doi: 10.1016/j.cclet.2022.02.038
Abstract:
Surface engineering that could modulate the surface shape to be endowed with the high specific surface ratio, abundant chemical dangling bonds and improved defects exposure is highly desired and needs further exploring. Here, we report a facile strategy of surface engineering on decorating the controllable segmented copper-iron nanowires arrays (Cu-Fe NWs) with their respective hydroxides. Specifically, the pristine segmented Cu-Fe NWs are firstly synthesized via sequentially electrodepositing Cu NWs and Fe NWs inside the nanochannels of anode aluminum oxide (AAO) template. Subsequently, the surface and interface of Cu-Fe NWs are wet-chemically etched, in which the metallic Cu and Fe are partially converted into Cu(OH)x nano-fibrous roots (NFRs) and FeO(OH)y nanoparticles (NPs), and finally decorate around the respective outer-surface of Cu NWs and Fe NWs segments. As one case of the applications in hydrogen evolution reaction (HER), our surface-modified Cu-Fe NWs exhibit improved catalytic activity compared with Fe NWs.
Surface engineering that could modulate the surface shape to be endowed with the high specific surface ratio, abundant chemical dangling bonds and improved defects exposure is highly desired and needs further exploring. Here, we report a facile strategy of surface engineering on decorating the controllable segmented copper-iron nanowires arrays (Cu-Fe NWs) with their respective hydroxides. Specifically, the pristine segmented Cu-Fe NWs are firstly synthesized via sequentially electrodepositing Cu NWs and Fe NWs inside the nanochannels of anode aluminum oxide (AAO) template. Subsequently, the surface and interface of Cu-Fe NWs are wet-chemically etched, in which the metallic Cu and Fe are partially converted into Cu(OH)x nano-fibrous roots (NFRs) and FeO(OH)y nanoparticles (NPs), and finally decorate around the respective outer-surface of Cu NWs and Fe NWs segments. As one case of the applications in hydrogen evolution reaction (HER), our surface-modified Cu-Fe NWs exhibit improved catalytic activity compared with Fe NWs.
2022, 33(8): 4021-4025
doi: 10.1016/j.cclet.2021.11.091
Abstract:
Dielectric elastomers (DEs) have drawn much attention owing to their application prospects in artificial muscles and soft robotics, it is still a big challenge to prepare DEs with high electromechanical performances. This work reports a highly stretchable poly(thioether)-b-polysiloxane-b-poly(thioether) triblock copolymer based homogenous DEs with high electromechanical properties. The triblock copolymer (PSiPGE) was synthesized through the ring-opening polymerization (ROP) of phenyl glycidyl ether (PGE) and carbonyl sulfide (COS) catalyzed by silicon alkoxides. The dipoles (benzene rings) on the side groups of PSiPGE improved the dipole polarizations and the phase separation structure of this triblock copolymer enhanced the interfacial polarizations between poly(thioether) and polysiloxane, and thus improving the dielectric constant (ε', up to 5.8). In addition, the PSiPGE exhibited low elastic modulus (Y, 0.04 MPa), and thus possessed high electromechanical sensitivity (β, ~145 MPa−1) which is much higher than that of most homogenous DEs. This work provides a new strategy to construct homogenous DEs with excellent electromechanical performances, leading to a greater application aspect in the actuated devices.
Dielectric elastomers (DEs) have drawn much attention owing to their application prospects in artificial muscles and soft robotics, it is still a big challenge to prepare DEs with high electromechanical performances. This work reports a highly stretchable poly(thioether)-b-polysiloxane-b-poly(thioether) triblock copolymer based homogenous DEs with high electromechanical properties. The triblock copolymer (PSiPGE) was synthesized through the ring-opening polymerization (ROP) of phenyl glycidyl ether (PGE) and carbonyl sulfide (COS) catalyzed by silicon alkoxides. The dipoles (benzene rings) on the side groups of PSiPGE improved the dipole polarizations and the phase separation structure of this triblock copolymer enhanced the interfacial polarizations between poly(thioether) and polysiloxane, and thus improving the dielectric constant (ε', up to 5.8). In addition, the PSiPGE exhibited low elastic modulus (Y, 0.04 MPa), and thus possessed high electromechanical sensitivity (β, ~145 MPa−1) which is much higher than that of most homogenous DEs. This work provides a new strategy to construct homogenous DEs with excellent electromechanical performances, leading to a greater application aspect in the actuated devices.
2022, 33(8): 4026-4032
doi: 10.1016/j.cclet.2021.12.003
Abstract:
To obtain high-efficiency flame retardancy of epoxy resins, a cyclophosphazene derivative tri-(o-henylenediamino)cyclotriphosphazene (3ACP) was successfully synthesized and used as a curing agent for the thermosetting of an epoxy resin system. The flame retardant properties, thermal stability, and pyrolysis mechanism of the resultant thermosets were investigated in detail. The experiments indicated that the synthesized thermoset achieved a UL-94 V-0 rate under a vertical burning test as well as a limiting oxygen index (LOI) of 29.2%, which was able to reach V-0 even when a small amount of 3ACP was incorporated. Scanning electronic microscopic observation demonstrated that the char residue of the thermosets was extremely expanded after the vertical flame test. Thermal analysis showed that the samples had a lower initial decomposition temperature when 3ACP was introduced into the epoxy resin systems. This indicates that the carbonization ability of the thermosets was significantly improved at elevated temperatures. In addition, the incorporation of 3ACP can effectively suppress the release of combustible gases during the pyrolysis process, and the decomposition of E-44/DDS-3ACP curing systems also promotes the formation of polyphosphoramides charred layer in the condensed phase. The investigation on the chemical structures of both the gaseous and condensed phase pyrolysis process confirmed the flame-retardant mechanism of the 3ACP-cured epoxy resins. Therefore, the nonflammable halogen-free epoxy resin developed in this study has potential applications in electric and electronic fields for environment protection and human health.
To obtain high-efficiency flame retardancy of epoxy resins, a cyclophosphazene derivative tri-(o-henylenediamino)cyclotriphosphazene (3ACP) was successfully synthesized and used as a curing agent for the thermosetting of an epoxy resin system. The flame retardant properties, thermal stability, and pyrolysis mechanism of the resultant thermosets were investigated in detail. The experiments indicated that the synthesized thermoset achieved a UL-94 V-0 rate under a vertical burning test as well as a limiting oxygen index (LOI) of 29.2%, which was able to reach V-0 even when a small amount of 3ACP was incorporated. Scanning electronic microscopic observation demonstrated that the char residue of the thermosets was extremely expanded after the vertical flame test. Thermal analysis showed that the samples had a lower initial decomposition temperature when 3ACP was introduced into the epoxy resin systems. This indicates that the carbonization ability of the thermosets was significantly improved at elevated temperatures. In addition, the incorporation of 3ACP can effectively suppress the release of combustible gases during the pyrolysis process, and the decomposition of E-44/DDS-3ACP curing systems also promotes the formation of polyphosphoramides charred layer in the condensed phase. The investigation on the chemical structures of both the gaseous and condensed phase pyrolysis process confirmed the flame-retardant mechanism of the 3ACP-cured epoxy resins. Therefore, the nonflammable halogen-free epoxy resin developed in this study has potential applications in electric and electronic fields for environment protection and human health.
2022, 33(8): 4033-4036
doi: 10.1016/j.cclet.2021.12.051
Abstract:
Rational construction of fine-tuning and precisely controllable topological nanostructures based on supramolecular self-assembly system remains a challenge. Herein, coumarin-12-crown-4 (1) as a building block was synthesized by one-pot method and showed reversible high stereo-selective photodimerization (anti-head-to-head dimer (anti-HH-1): syn-head-to-head dimer (syn-HH-1) = 10.8:1) and photocleavage. Helical nanobelts were formed by the self-assembly of 1 through asymmetrical H-bonds, which were in concordance with the crystal state superstructure. Upon irradiation with 365 nm light, these nanobelts transformed into nanoballs which were constructed by three building blocks. Further, we investigated the photoreaction of 1 and got two pure covalent dimers (anti-HH-1 and syn-HH-1). The anti-HH-1 self-assembled into hollow micro-vesicles. The transformation of superstructures based on photo-controlled multiple blocks shines a light to the research on the relationship between molecules and superstructures.
Rational construction of fine-tuning and precisely controllable topological nanostructures based on supramolecular self-assembly system remains a challenge. Herein, coumarin-12-crown-4 (1) as a building block was synthesized by one-pot method and showed reversible high stereo-selective photodimerization (anti-head-to-head dimer (anti-HH-1): syn-head-to-head dimer (syn-HH-1) = 10.8:1) and photocleavage. Helical nanobelts were formed by the self-assembly of 1 through asymmetrical H-bonds, which were in concordance with the crystal state superstructure. Upon irradiation with 365 nm light, these nanobelts transformed into nanoballs which were constructed by three building blocks. Further, we investigated the photoreaction of 1 and got two pure covalent dimers (anti-HH-1 and syn-HH-1). The anti-HH-1 self-assembled into hollow micro-vesicles. The transformation of superstructures based on photo-controlled multiple blocks shines a light to the research on the relationship between molecules and superstructures.
2022, 33(8): 4037-4042
doi: 10.1016/j.cclet.2021.12.022
Abstract:
At present, replacing the liquid electrolyte in a lithium metal battery with a solid electrolyte is considered to be one of the most powerful strategies to avoid potential safety hazards. Composite solid electrolytes (CPEs) have excellent ionic conductivity and flexibility owing to the combination of functional inorganic materials and polymer solid electrolytes (SPEs). Nevertheless, the ionic conductivity of CPEs is still lower than those of commercial liquid electrolytes, so the development of high-performance CPEs has important practical significance. Herein, a novel fast lithium-ion conductor material LiTa2PO8 was first filled into poly(ethylene oxide) (PEO)-based SPE, and the optimal ionic conductivity was achieved by filling different concentrations (the ionic conductivity is 4.61 × 10−4 S/cm with a filling content of 15 wt% at 60 ℃). The enhancement in ionic conductivity is due to the improvement of PEO chain movement and the promotion of LiTFSI dissociation by LiTa2PO8. In addition, LiTa2PO8 also takes the key in enhancing the mechanical strength and thermal stability of CPEs. The assembled LiFePO4 solid-state lithium metal battery displays better rate performance (the specific capacities are as high as 157.3, 152, 142.6, 105 and 53.1 mAh/g under 0.1, 0.2, 0.5, 1 and 2 C at 60 ℃, respectively) and higher cycle performance (the capacity retention rate is 86.5% after 200 cycles at 0.5 C and 60 ℃). This research demonstrates the feasibility of LiTa2PO8 as a filler to improve the performance of CPEs, which may provide a fresh platform for developing more advanced solid-state electrolytes.
At present, replacing the liquid electrolyte in a lithium metal battery with a solid electrolyte is considered to be one of the most powerful strategies to avoid potential safety hazards. Composite solid electrolytes (CPEs) have excellent ionic conductivity and flexibility owing to the combination of functional inorganic materials and polymer solid electrolytes (SPEs). Nevertheless, the ionic conductivity of CPEs is still lower than those of commercial liquid electrolytes, so the development of high-performance CPEs has important practical significance. Herein, a novel fast lithium-ion conductor material LiTa2PO8 was first filled into poly(ethylene oxide) (PEO)-based SPE, and the optimal ionic conductivity was achieved by filling different concentrations (the ionic conductivity is 4.61 × 10−4 S/cm with a filling content of 15 wt% at 60 ℃). The enhancement in ionic conductivity is due to the improvement of PEO chain movement and the promotion of LiTFSI dissociation by LiTa2PO8. In addition, LiTa2PO8 also takes the key in enhancing the mechanical strength and thermal stability of CPEs. The assembled LiFePO4 solid-state lithium metal battery displays better rate performance (the specific capacities are as high as 157.3, 152, 142.6, 105 and 53.1 mAh/g under 0.1, 0.2, 0.5, 1 and 2 C at 60 ℃, respectively) and higher cycle performance (the capacity retention rate is 86.5% after 200 cycles at 0.5 C and 60 ℃). This research demonstrates the feasibility of LiTa2PO8 as a filler to improve the performance of CPEs, which may provide a fresh platform for developing more advanced solid-state electrolytes.
2022, 33(8): 4043-4047
doi: 10.1016/j.cclet.2021.12.037
Abstract:
As a member of the curcuminoid compound family, curcumin (Cur) has many interesting therapeutic properties. However, its low aqueous solubility and stability have resulted in poor bioavailability and restricted clinical efficacy. Based on size matching, β-cyclodextrin polymer (β-CDP), with its hydrophilic polymer chains and hydrophobic cavities, can form an inclusion complex with Cur. To improve the water solubility and stability of Cur, a simple and eco-friendly grinding method was designed to form β-CDP inclusion complexes. According to the Boltzmann–Hamel's method and Job's method, the molar ratio of the β-CD unit in β-CDP to Cur was determined to be 1 : 1. The diffusion coefficient and diffusion activation energy of Cur-β-CDP were calculated in an electrochemical study. This supramolecular complex worked well in vitro to inhibit the proliferation of hepatoma carcinoma cells HepG2. Remarkably, this method visibly reduced the undesirable side effects on normal cells, without weakening the anti-cancer activity of the drugs. We expect that the obtained host–guest complex will provide a new approach for delivering natural drug molecules, having low water solubility.
As a member of the curcuminoid compound family, curcumin (Cur) has many interesting therapeutic properties. However, its low aqueous solubility and stability have resulted in poor bioavailability and restricted clinical efficacy. Based on size matching, β-cyclodextrin polymer (β-CDP), with its hydrophilic polymer chains and hydrophobic cavities, can form an inclusion complex with Cur. To improve the water solubility and stability of Cur, a simple and eco-friendly grinding method was designed to form β-CDP inclusion complexes. According to the Boltzmann–Hamel's method and Job's method, the molar ratio of the β-CD unit in β-CDP to Cur was determined to be 1 : 1. The diffusion coefficient and diffusion activation energy of Cur-β-CDP were calculated in an electrochemical study. This supramolecular complex worked well in vitro to inhibit the proliferation of hepatoma carcinoma cells HepG2. Remarkably, this method visibly reduced the undesirable side effects on normal cells, without weakening the anti-cancer activity of the drugs. We expect that the obtained host–guest complex will provide a new approach for delivering natural drug molecules, having low water solubility.
2022, 33(8): 4048-4052
doi: 10.1016/j.cclet.2021.12.038
Abstract:
A series of pyrazolone derivatives bearing a tetrasubstituted chiral center were prepared by virtue of a Lewis acid-catalyzed Friedel-Crafts reaction, in which a chiral copper complex was employed as the catalyst. This reaction can be carried out smoothly under mild condition to afford the pyrazolone derivatives with high yields (up to 85%) and excellent enantioselectivities (up to 99%). In addition, the gram scale synthesis proved the practicality of this reaction.
A series of pyrazolone derivatives bearing a tetrasubstituted chiral center were prepared by virtue of a Lewis acid-catalyzed Friedel-Crafts reaction, in which a chiral copper complex was employed as the catalyst. This reaction can be carried out smoothly under mild condition to afford the pyrazolone derivatives with high yields (up to 85%) and excellent enantioselectivities (up to 99%). In addition, the gram scale synthesis proved the practicality of this reaction.
2022, 33(8): 4053-4056
doi: 10.1016/j.cclet.2022.01.072
Abstract:
Enterocytozoon hepatopenaei (EHP) infection has seriously affected prawn culture globally. The symptoms of the infection are not apparent, and traditional detection methods are time consuming and low in accuracy. We developed a new onsite rapid testing device (size 18.8 × 16.7 × 6.6 cm3) for EHP based on magnesium pyrophosphate precipitation and facilitated by loop mediated isothermal amplification (LAMP). The design and fabrication of the device enables efficient light absorbance. The device has a highly sensitive detector, high-precision thermal controller, and humanized touch screen. The temperature control precision of the device is 0.2–0.3 ℃ at 60 ℃, 63 ℃, and 65 ℃. The coefficients of variation values (CVV) of the luminous power in one channel at light on and off were found to be 0.0097 and 0.0014, respectively, within 1 h. The CVV of the background, luminous power, and values of eight PCR tubes filled with pure water were all less than 5%. In the EHP experiment, eight samples (including seven positive and one negative) confirmed the effectiveness of the device, and four positive and four negative samples verified whether cross-contamination exists. Among them, the rise time of the curve was about 15 min. These results assert that the developed device exhibits enhanced stability and uniformity and has excellent performance with high sensitivity, good specificity, and low testing time. Moreover, the optimal and minimum absorbance range was 555–655 nm for monitoring the production of LAMP.
Enterocytozoon hepatopenaei (EHP) infection has seriously affected prawn culture globally. The symptoms of the infection are not apparent, and traditional detection methods are time consuming and low in accuracy. We developed a new onsite rapid testing device (size 18.8 × 16.7 × 6.6 cm3) for EHP based on magnesium pyrophosphate precipitation and facilitated by loop mediated isothermal amplification (LAMP). The design and fabrication of the device enables efficient light absorbance. The device has a highly sensitive detector, high-precision thermal controller, and humanized touch screen. The temperature control precision of the device is 0.2–0.3 ℃ at 60 ℃, 63 ℃, and 65 ℃. The coefficients of variation values (CVV) of the luminous power in one channel at light on and off were found to be 0.0097 and 0.0014, respectively, within 1 h. The CVV of the background, luminous power, and values of eight PCR tubes filled with pure water were all less than 5%. In the EHP experiment, eight samples (including seven positive and one negative) confirmed the effectiveness of the device, and four positive and four negative samples verified whether cross-contamination exists. Among them, the rise time of the curve was about 15 min. These results assert that the developed device exhibits enhanced stability and uniformity and has excellent performance with high sensitivity, good specificity, and low testing time. Moreover, the optimal and minimum absorbance range was 555–655 nm for monitoring the production of LAMP.
2022, 33(8): 4057-4060
doi: 10.1016/j.cclet.2021.12.053
Abstract:
Herein, we report a practical electro-reductive protocol for the direct C–H cyanoalkylation of quinoxalin-2(1H)-ones via iminyl radical-mediated ring opening. These mild reactions proceed under metal-, reductant-, and reagent-free conditions to provide synthetically useful cyanoalkylated quinoxalin-2(1H)-ones.
Herein, we report a practical electro-reductive protocol for the direct C–H cyanoalkylation of quinoxalin-2(1H)-ones via iminyl radical-mediated ring opening. These mild reactions proceed under metal-, reductant-, and reagent-free conditions to provide synthetically useful cyanoalkylated quinoxalin-2(1H)-ones.
2022, 33(8): 4061-4063
doi: 10.1016/j.cclet.2021.12.068
Abstract:
A hydrogen fluoride-free and chloro-free method for synthesizing LiPF6 was developed. Employing CaF2 as the direct fluorinating reagent instead of hydrogen fluoride made it much safer and more environment-friendly than conventional methods and reduced the metal residues in product owing to the relatively low-acid reaction conditions less corrosive to equipments. The use of P2O5 as phosphorus source instead of traditionally employed PCl5 significantly reduced the chloro residue in product. Ca(H2PO4)2, the only by-product of the process, could be easily converted into Ca3(PO4)2, a best-selling chemical. The above advantages not only reduce the production costs by ca. 20%, but also significantly improve the product purity. The fluorine-oxygen exchange reaction is a completely new technique for LiPF6 production and may bring about technological revolution in the related industry.
A hydrogen fluoride-free and chloro-free method for synthesizing LiPF6 was developed. Employing CaF2 as the direct fluorinating reagent instead of hydrogen fluoride made it much safer and more environment-friendly than conventional methods and reduced the metal residues in product owing to the relatively low-acid reaction conditions less corrosive to equipments. The use of P2O5 as phosphorus source instead of traditionally employed PCl5 significantly reduced the chloro residue in product. Ca(H2PO4)2, the only by-product of the process, could be easily converted into Ca3(PO4)2, a best-selling chemical. The above advantages not only reduce the production costs by ca. 20%, but also significantly improve the product purity. The fluorine-oxygen exchange reaction is a completely new technique for LiPF6 production and may bring about technological revolution in the related industry.
2022, 33(8): 4064-4068
doi: 10.1016/j.cclet.2021.12.072
Abstract:
A Ru(Ⅲ)-catalyzed annulation reaction of 2-aminoaromatic aldehydes (ketones) and isoxazoles to afford diverse 3-cyanoquinolines has been developed. Notably, isoxazole acted as a cyclization reagent and nontoxic cyano source via N-O bond cleavage and fragmentation. Variously substituted (especially 6- or 7-substituted) quinolines could be easily afforded. This procedure features wide functional group compatibility, efficiency and avoiding toxic cyano source. Meanwhile, this protocol could be successfully applied to scale-up synthesis. Further chemical transformations of 3-cyanoquinoline could give some valuable skeletons, demonstrating its potential in synthetic application
A Ru(Ⅲ)-catalyzed annulation reaction of 2-aminoaromatic aldehydes (ketones) and isoxazoles to afford diverse 3-cyanoquinolines has been developed. Notably, isoxazole acted as a cyclization reagent and nontoxic cyano source via N-O bond cleavage and fragmentation. Variously substituted (especially 6- or 7-substituted) quinolines could be easily afforded. This procedure features wide functional group compatibility, efficiency and avoiding toxic cyano source. Meanwhile, this protocol could be successfully applied to scale-up synthesis. Further chemical transformations of 3-cyanoquinoline could give some valuable skeletons, demonstrating its potential in synthetic application
2022, 33(8): 4069-4073
doi: 10.1016/j.cclet.2022.03.090
Abstract:
Three polymorphs (forms Ⅰ, Ⅱ and Ⅴ) of isonicotinamide (INA) were mechanically flexible and exhibited one-dimensional (1D) plasticity. Anisotropic intermolecular interactions contribute to the plasticity of single crystals: weak dispersive interactions between slip planes such as 1D columns in forms Ⅰ and Ⅱ or 2D layers in form Ⅴ were stabilized by strong hydrogen bonds, allowing the layer or column's surface to glide smoothly without hindrance. The disparity of intermolecular interactions on plastic properties of INA polymorphic crystals was confirmed by energy framework analysis, nanoindentation tests and micro-Raman spectroscopy. The crystal which exhibits plastic property provides a promising application in pharmaceuticals and material sciences.
Three polymorphs (forms Ⅰ, Ⅱ and Ⅴ) of isonicotinamide (INA) were mechanically flexible and exhibited one-dimensional (1D) plasticity. Anisotropic intermolecular interactions contribute to the plasticity of single crystals: weak dispersive interactions between slip planes such as 1D columns in forms Ⅰ and Ⅱ or 2D layers in form Ⅴ were stabilized by strong hydrogen bonds, allowing the layer or column's surface to glide smoothly without hindrance. The disparity of intermolecular interactions on plastic properties of INA polymorphic crystals was confirmed by energy framework analysis, nanoindentation tests and micro-Raman spectroscopy. The crystal which exhibits plastic property provides a promising application in pharmaceuticals and material sciences.
2022, 33(8): 4074-4078
doi: 10.1016/j.cclet.2021.12.050
Abstract:
We report a Ni-catalyzed three-component cross-electrophile coupling of alkynes with alkenyl halides and fluoroalkyl halides to generate fluoroalkyl-incorporated 1,3-dienes. This mild and operationally simple protocol is distinguished by its broad substrate scope and excellent chemo-, regio-, and stereo-selectivity, offering a new and organometallic agent-free platform for the construction of fluoroalkyl-incorporated diene motifs. Preliminary mechanistic studies have been conducted to probe the potential reaction pathway.
We report a Ni-catalyzed three-component cross-electrophile coupling of alkynes with alkenyl halides and fluoroalkyl halides to generate fluoroalkyl-incorporated 1,3-dienes. This mild and operationally simple protocol is distinguished by its broad substrate scope and excellent chemo-, regio-, and stereo-selectivity, offering a new and organometallic agent-free platform for the construction of fluoroalkyl-incorporated diene motifs. Preliminary mechanistic studies have been conducted to probe the potential reaction pathway.
2022, 33(8): 4079-4083
doi: 10.1016/j.cclet.2022.01.043
Abstract:
Nanocrystals are of great value in delivering poorly soluble drugs as a technique enables enhanced dissolution and bioavailability. The bottom-up technique allows better control of particle properties. However, the commonly used organic solvents are hazardous to environment and operators, and always lead to large particle size and wide size distribution due to failure on controlling the nucleation and crystal growth. The situation is exacerbated in scale-up production. Therefore, in the proof-of-concept study, we evaluated the feasibility of green and controllable fabrication of drug nanocrystals by using biocompatible ionic liquids (ILs) as solvents. Choline based ILs (Ch-ILs) were synthesized via metathesis reactions. Pure paclitaxel nanocrystals of high quality were obtained from Ch-ILs with surface tension higher than 42 mN/m. The sizes were below 250 nm, while the polydispersity indexes were lower than 0.25. Compared with ethanol, choline lactate is superior in controlling the size of the nanocrystals in scale-up production, where the drug concentration was increased by 6 times. The underlying mechanism may be due to the high viscosity and low surface tension of the ILs, which are supposed to benefit homogeneous and burst nucleation. Ch-ILs can be recycled from the process and recovery rate reached 91.1%. Moreover, the applicability of the green technique was validated in a wider range of model drugs and Ch-ILs. In conclusion, ILs are potent solvents in bottom-up technique for green and controllable fabrication of nanocrystals.
Nanocrystals are of great value in delivering poorly soluble drugs as a technique enables enhanced dissolution and bioavailability. The bottom-up technique allows better control of particle properties. However, the commonly used organic solvents are hazardous to environment and operators, and always lead to large particle size and wide size distribution due to failure on controlling the nucleation and crystal growth. The situation is exacerbated in scale-up production. Therefore, in the proof-of-concept study, we evaluated the feasibility of green and controllable fabrication of drug nanocrystals by using biocompatible ionic liquids (ILs) as solvents. Choline based ILs (Ch-ILs) were synthesized via metathesis reactions. Pure paclitaxel nanocrystals of high quality were obtained from Ch-ILs with surface tension higher than 42 mN/m. The sizes were below 250 nm, while the polydispersity indexes were lower than 0.25. Compared with ethanol, choline lactate is superior in controlling the size of the nanocrystals in scale-up production, where the drug concentration was increased by 6 times. The underlying mechanism may be due to the high viscosity and low surface tension of the ILs, which are supposed to benefit homogeneous and burst nucleation. Ch-ILs can be recycled from the process and recovery rate reached 91.1%. Moreover, the applicability of the green technique was validated in a wider range of model drugs and Ch-ILs. In conclusion, ILs are potent solvents in bottom-up technique for green and controllable fabrication of nanocrystals.
2022, 33(8): 4084-4088
doi: 10.1016/j.cclet.2022.01.051
Abstract:
Sugar-dependent targeting and immune adjuvant effects of hyperbranched glycosylated polypeptide nanoparticles were disclosed for ovalbumin (OVA) delivery system. The mannose-coated polypeptide nanoparticles can induce strongest targeting and immune adjuvant effects to macrophages than those glucose/lactose-coated ones, which effectively transported OVA into cells and facilitated OVA subcellular escape from endolysosomes into cytoplasm with the assistance of UV irradiation or intracellular acidic pH.
Sugar-dependent targeting and immune adjuvant effects of hyperbranched glycosylated polypeptide nanoparticles were disclosed for ovalbumin (OVA) delivery system. The mannose-coated polypeptide nanoparticles can induce strongest targeting and immune adjuvant effects to macrophages than those glucose/lactose-coated ones, which effectively transported OVA into cells and facilitated OVA subcellular escape from endolysosomes into cytoplasm with the assistance of UV irradiation or intracellular acidic pH.
2022, 33(8): 4089-4095
doi: 10.1016/j.cclet.2022.01.071
Abstract:
With an intensive understanding of the mechanism of immune system, developing a therapeutic tumor vaccine is one of the most perspective strategy of cancer immunotherapy. In this study, we report a facile approach to prepare graphene oxide (GO)-based therapeutic cancer-nanovaccine. The model antigen (ovalbumin, OVA) and adjuvant (CpG ODN), are conjugated with GO-PEI nanosheet through electrostatic interaction. The addition of PEG can improve biocompatibility and prevent nanoparticle aggregation. The prepared GO-based nanovaccine, GO-PEI-OVA-PEG-CpG, exhibits good biocompatibility and low toxicity both in vivo and in vitro. More importantly, it can efficiently induce the maturation of dendritic cells (DCs), the enhancement of antigen cross-presentation ability, and the amplification of cytokine production of immune cells. Impressively, this nanovaccine shows a remarkable therapeutic effect against pre-established B16-OVA-melanoma tumors, which can significantly inhibit tumor growth and prolong the survival time of the OVA-expressed tumor-bearing mice. Moreover, combining GO-PEI-OVA-PEG-CpG with NLG919, an IDO-1 (indoleamine-2,3-dioxygenase) inhibitor which can regulate the tumor microenvironment, displays a synergistic therapeutic effect. These findings indicate the GO-PEI-OVA-PEG-CpG nanovaccine actively induces an antigen-specific antitumor immune response and it combined with NLG919 could achieve better therapeutic outcomes.
With an intensive understanding of the mechanism of immune system, developing a therapeutic tumor vaccine is one of the most perspective strategy of cancer immunotherapy. In this study, we report a facile approach to prepare graphene oxide (GO)-based therapeutic cancer-nanovaccine. The model antigen (ovalbumin, OVA) and adjuvant (CpG ODN), are conjugated with GO-PEI nanosheet through electrostatic interaction. The addition of PEG can improve biocompatibility and prevent nanoparticle aggregation. The prepared GO-based nanovaccine, GO-PEI-OVA-PEG-CpG, exhibits good biocompatibility and low toxicity both in vivo and in vitro. More importantly, it can efficiently induce the maturation of dendritic cells (DCs), the enhancement of antigen cross-presentation ability, and the amplification of cytokine production of immune cells. Impressively, this nanovaccine shows a remarkable therapeutic effect against pre-established B16-OVA-melanoma tumors, which can significantly inhibit tumor growth and prolong the survival time of the OVA-expressed tumor-bearing mice. Moreover, combining GO-PEI-OVA-PEG-CpG with NLG919, an IDO-1 (indoleamine-2,3-dioxygenase) inhibitor which can regulate the tumor microenvironment, displays a synergistic therapeutic effect. These findings indicate the GO-PEI-OVA-PEG-CpG nanovaccine actively induces an antigen-specific antitumor immune response and it combined with NLG919 could achieve better therapeutic outcomes.
2022, 33(8): 4096-4100
doi: 10.1016/j.cclet.2022.01.040
Abstract:
Aflatoxin B1 (AFB1) is one of the most common mycotoxins that threatens human health. As single-stranded oligonucleotides with high affinity and specificity, aptamers have incomparable effect on the targeted detection of AFB1. Herein, after 11 rounds of selection and analysis using a modified affinity chromatography-based SELEX strategy, the truncated 37 nt aptamer AF11–2 was successfully obtained. The aptamer shows good detection performance for AFB1, and can sensitively detect AFB1 in the range of 100–1000 nmol/L, with a detection limit of 42 nmol/L. In the detection of pretreated edible peanut oil samples, AF11–2 aptamer also showed a high recovery rate and good stability for AFB1, and achieved satisfactory results. In addition, AF11–2 aptamer can significantly enhance the fluorescence ability of AFB1, which is not available in traditional Afla17–2–3 aptamer. After molecular docking analysis, it was found that AF11–2 and Afla17–2–3 had different nucleotide binding sites for AFB1. Afla17–2–3 binds to the carbonyl O of AFB1, while AF11–2 binds to the pyrrolic O of AFB1, which may be the main reason that AF11–2 can enhance the fluorescence of AFB1.
Aflatoxin B1 (AFB1) is one of the most common mycotoxins that threatens human health. As single-stranded oligonucleotides with high affinity and specificity, aptamers have incomparable effect on the targeted detection of AFB1. Herein, after 11 rounds of selection and analysis using a modified affinity chromatography-based SELEX strategy, the truncated 37 nt aptamer AF11–2 was successfully obtained. The aptamer shows good detection performance for AFB1, and can sensitively detect AFB1 in the range of 100–1000 nmol/L, with a detection limit of 42 nmol/L. In the detection of pretreated edible peanut oil samples, AF11–2 aptamer also showed a high recovery rate and good stability for AFB1, and achieved satisfactory results. In addition, AF11–2 aptamer can significantly enhance the fluorescence ability of AFB1, which is not available in traditional Afla17–2–3 aptamer. After molecular docking analysis, it was found that AF11–2 and Afla17–2–3 had different nucleotide binding sites for AFB1. Afla17–2–3 binds to the carbonyl O of AFB1, while AF11–2 binds to the pyrrolic O of AFB1, which may be the main reason that AF11–2 can enhance the fluorescence of AFB1.
2022, 33(8): 4101-4106
doi: 10.1016/j.cclet.2022.01.049
Abstract:
Fluorescence (FL) imaging guided photodynamic therapy (PDT) is becoming highly desirable for personalized therapy and precision medicine. In this study, fluorescent polymer nanoparticles TCPP@PEI/PGA were facilely synthesized through electrostatic interaction-mediated self-assembly of porphyrins tetra(4-carboxyphenyl)porphine (TCPP) and polyethylenimine (PEI), and subsequent surface modification with γ-poly(glutamic acid) (γ-PGA). TCPP served a dual function as the FL imaging probe and the photosensitizer. The as-prepared TCPP@PEI/PGA nanoparticles showed excellent water-solubility and biocompatibility, while having outstanding capabilities of in vivo bioimaging and 1O2 generation. FL bioimaging of mice and effective killing of CT 26 cells as well as CT 26 tumor-bearing mice upon laser irradiation were successfully demonstrated when using TCPP@PEI/PGA as theranostic nanoprobes. This study provides a simple but robust method to design and synthesize porphyrin-based polymer nanoparticles for theranostics.
Fluorescence (FL) imaging guided photodynamic therapy (PDT) is becoming highly desirable for personalized therapy and precision medicine. In this study, fluorescent polymer nanoparticles TCPP@PEI/PGA were facilely synthesized through electrostatic interaction-mediated self-assembly of porphyrins tetra(4-carboxyphenyl)porphine (TCPP) and polyethylenimine (PEI), and subsequent surface modification with γ-poly(glutamic acid) (γ-PGA). TCPP served a dual function as the FL imaging probe and the photosensitizer. The as-prepared TCPP@PEI/PGA nanoparticles showed excellent water-solubility and biocompatibility, while having outstanding capabilities of in vivo bioimaging and 1O2 generation. FL bioimaging of mice and effective killing of CT 26 cells as well as CT 26 tumor-bearing mice upon laser irradiation were successfully demonstrated when using TCPP@PEI/PGA as theranostic nanoprobes. This study provides a simple but robust method to design and synthesize porphyrin-based polymer nanoparticles for theranostics.
2022, 33(8): 4107-4110
doi: 10.1016/j.cclet.2021.11.036
Abstract:
Novel peptide-fentanyl analogue conjugates were synthesized by the covalent coupling of carfentanyl derivatives to the C-terminus or N-terminus of the conformationally constrained dermorphin tetrapeptide BVD03 via a chemical linker. The carfentanyl-related analogues displayed distinct binding and functional activities at µ/δ opioid receptors (MOR/DOR) and antinociceptive effects when conjugated to the peptide. The most potent compound, SW-LJ-11, displayed mixed MOR/DOR agonist properties in the low nanomolar range and significant analgesic efficacy in vivo in four classic mouse models of pain. Interestingly, SW-LJ-11 did not exhibit any physical dependence or respiratory depression, in contrast to an equipotent analgesic dose of morphine or BVD03, indicating that the use of opioid peptide–fentanyl analogue conjugates as dual MOR/DOR agonists may be a promising strategy for obtaining safer opioids.
Novel peptide-fentanyl analogue conjugates were synthesized by the covalent coupling of carfentanyl derivatives to the C-terminus or N-terminus of the conformationally constrained dermorphin tetrapeptide BVD03 via a chemical linker. The carfentanyl-related analogues displayed distinct binding and functional activities at µ/δ opioid receptors (MOR/DOR) and antinociceptive effects when conjugated to the peptide. The most potent compound, SW-LJ-11, displayed mixed MOR/DOR agonist properties in the low nanomolar range and significant analgesic efficacy in vivo in four classic mouse models of pain. Interestingly, SW-LJ-11 did not exhibit any physical dependence or respiratory depression, in contrast to an equipotent analgesic dose of morphine or BVD03, indicating that the use of opioid peptide–fentanyl analogue conjugates as dual MOR/DOR agonists may be a promising strategy for obtaining safer opioids.
2022, 33(8): 4111-4115
doi: 10.1016/j.cclet.2022.01.042
Abstract:
Red emissive carbon dots (CDs) are highly desired for biological applications. However, serious luminescence quenching of red emissive CDs in aqueous solution greatly hinders their application in high performance biological imaging. Herein, we reported a facile strategy to realize enhanced red emission of CDs in aqueous solution by surface modification with polyetherimide (PEI) via microwave heating method. High photoluminescence quantum yield (PLQY) of 25% was realized from the PEI functionalized CDs (CDs@PEI) in aqueous solution. The proposed PEI functionalization strategy not only protects the red emission against water molecules quenching, but also reverses the surface charges from negativity to positivity to promote cellular uptake of CDs, leading to clear cell imaging in red fluorescence region. More important, CDs@PEI exhibits much better photostability than commercial red emissive dye (MitoTracker red) in cell fluorescent imaging. Potential application of CDs@PEI on fast staining of cells for clonogenic assay has also been demonstrated.
Red emissive carbon dots (CDs) are highly desired for biological applications. However, serious luminescence quenching of red emissive CDs in aqueous solution greatly hinders their application in high performance biological imaging. Herein, we reported a facile strategy to realize enhanced red emission of CDs in aqueous solution by surface modification with polyetherimide (PEI) via microwave heating method. High photoluminescence quantum yield (PLQY) of 25% was realized from the PEI functionalized CDs (CDs@PEI) in aqueous solution. The proposed PEI functionalization strategy not only protects the red emission against water molecules quenching, but also reverses the surface charges from negativity to positivity to promote cellular uptake of CDs, leading to clear cell imaging in red fluorescence region. More important, CDs@PEI exhibits much better photostability than commercial red emissive dye (MitoTracker red) in cell fluorescent imaging. Potential application of CDs@PEI on fast staining of cells for clonogenic assay has also been demonstrated.
2022, 33(8): 4116-4120
doi: 10.1016/j.cclet.2022.01.053
Abstract:
The paper describes a kind of truly full-color photoluminescence (PL) CDs. The CDs were prepared by using one-pot hydrothermally heating citric acid and formamide at 200 ℃ for 2 h. The CDs have three fluorescent centers at blue, green, and red light region. Their color was regulated through two means, including changing excitation wavelengths or CDs concentrations. The emission maxima changed from blue to red with the increase of excitation wavelengths or CDs concentrations. The full-color PL behavior of the CDs was inherited and conserved in the solid polymer matrix, giving multicolor CDs/polymer films and light emitting diodes (LEDs). White-light LED (WLED) with the CIE coordinate approaching to (0.31, 0.32) were also achieved.
The paper describes a kind of truly full-color photoluminescence (PL) CDs. The CDs were prepared by using one-pot hydrothermally heating citric acid and formamide at 200 ℃ for 2 h. The CDs have three fluorescent centers at blue, green, and red light region. Their color was regulated through two means, including changing excitation wavelengths or CDs concentrations. The emission maxima changed from blue to red with the increase of excitation wavelengths or CDs concentrations. The full-color PL behavior of the CDs was inherited and conserved in the solid polymer matrix, giving multicolor CDs/polymer films and light emitting diodes (LEDs). White-light LED (WLED) with the CIE coordinate approaching to (0.31, 0.32) were also achieved.
2022, 33(8): 4121-4125
doi: 10.1016/j.cclet.2021.11.011
Abstract:
Two novel seco-polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperbenzones A (1) and B (2), were isolated from the roots of Hypericum beanii, together with one known biosynthetic congener 3. Compound 1 incorporates a 6/5/5 ring system with an unprecedented spiro[bicyclo[3.3.0]octane-3,1ʹ-cyclohexane]-2,2ʹ-dione motif. The structures of 1 and 2 were determined by a combination of high resolution electrospray ionization mass spectroscopy (HRESIMS), nuclear magnetic resonance (NMR) spectroscopic analyses, gage-independent atomic orbital (GIAO) NMR chemical shift calculation with DP4+ analyses, electronic circular dichroism (ECD) calculation, and X-ray diffraction analysis. A 1,2-seco retro-Claisen rearrangement from a bicyclo[3.3.1]nonane PPAP precursor and following chemodivergent radical cascade cyclizations are proposed as the key steps in the biosynthetic pathway to yield compounds 1 and 2. Biological investigations indicated that compounds 1 and 3 could decrease intracellular lipid accumulation in a palmitic acid-induced nonalcoholic steatohepatitis (NASH) cell model.
Two novel seco-polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperbenzones A (1) and B (2), were isolated from the roots of Hypericum beanii, together with one known biosynthetic congener 3. Compound 1 incorporates a 6/5/5 ring system with an unprecedented spiro[bicyclo[3.3.0]octane-3,1ʹ-cyclohexane]-2,2ʹ-dione motif. The structures of 1 and 2 were determined by a combination of high resolution electrospray ionization mass spectroscopy (HRESIMS), nuclear magnetic resonance (NMR) spectroscopic analyses, gage-independent atomic orbital (GIAO) NMR chemical shift calculation with DP4+ analyses, electronic circular dichroism (ECD) calculation, and X-ray diffraction analysis. A 1,2-seco retro-Claisen rearrangement from a bicyclo[3.3.1]nonane PPAP precursor and following chemodivergent radical cascade cyclizations are proposed as the key steps in the biosynthetic pathway to yield compounds 1 and 2. Biological investigations indicated that compounds 1 and 3 could decrease intracellular lipid accumulation in a palmitic acid-induced nonalcoholic steatohepatitis (NASH) cell model.
2022, 33(8): 4126-4132
doi: 10.1016/j.cclet.2021.11.065
Abstract:
Liquid biopsy is a highly promising method for non-invasive detection of tumor-associated nucleic acid fragments in body fluids but is challenged by the low abundance of nucleic acids of clinical interest and their sequence homology with the vast background of nucleic acids from healthy cells. Recently, programmable endonucleases such as clustered regularly interspaced short palindromic repeats (CRISPR) associated protein (Cas) and prokaryotic Argonautes have been successfully used to remove background nucleic acids and enrich mutant allele fractions, enabling their detection with deep next generation sequencing (NGS). However, the enrichment level achievable with these assays is limited by futile binding events and off-target cleavage. To overcome these shortcomings, we conceived a new assay (Programmable Enzyme-Assisted Selective Exponential Amplification, PASEA) that combines the cleavage of wild type alleles with concurrent polymerase amplification. While PASEA increases the numbers of both wild type and mutant alleles, the numbers of mutant alleles increase at much greater rates, allowing PASEA to achieve an unprecedented level of selective enrichment of targeted alleles. By combining CRISPR-Cas9 based cleavage with recombinase polymerase amplification, we converted samples with 0.01% somatic mutant allele fractions (MAFs) to products with 70% MAFs in a single step within 20 min, enabling inexpensive, rapid genotyping with such as Sanger sequencers. Furthermore, PASEA's extraordinary efficiency facilitates sensitive real-time detection of somatic mutant alleles at the point of care with custom designed Exo-RPA probes. Real-time PASEA' performance was proved equivalent to clinical amplification refractory mutation system (ARMS)-PCR and NGS when testing over hundred cancer patients' samples. This strategy has the potential to reduce the cost and time of cancer screening and genotyping, and to enable targeted therapies in resource-limited settings.
Liquid biopsy is a highly promising method for non-invasive detection of tumor-associated nucleic acid fragments in body fluids but is challenged by the low abundance of nucleic acids of clinical interest and their sequence homology with the vast background of nucleic acids from healthy cells. Recently, programmable endonucleases such as clustered regularly interspaced short palindromic repeats (CRISPR) associated protein (Cas) and prokaryotic Argonautes have been successfully used to remove background nucleic acids and enrich mutant allele fractions, enabling their detection with deep next generation sequencing (NGS). However, the enrichment level achievable with these assays is limited by futile binding events and off-target cleavage. To overcome these shortcomings, we conceived a new assay (Programmable Enzyme-Assisted Selective Exponential Amplification, PASEA) that combines the cleavage of wild type alleles with concurrent polymerase amplification. While PASEA increases the numbers of both wild type and mutant alleles, the numbers of mutant alleles increase at much greater rates, allowing PASEA to achieve an unprecedented level of selective enrichment of targeted alleles. By combining CRISPR-Cas9 based cleavage with recombinase polymerase amplification, we converted samples with 0.01% somatic mutant allele fractions (MAFs) to products with 70% MAFs in a single step within 20 min, enabling inexpensive, rapid genotyping with such as Sanger sequencers. Furthermore, PASEA's extraordinary efficiency facilitates sensitive real-time detection of somatic mutant alleles at the point of care with custom designed Exo-RPA probes. Real-time PASEA' performance was proved equivalent to clinical amplification refractory mutation system (ARMS)-PCR and NGS when testing over hundred cancer patients' samples. This strategy has the potential to reduce the cost and time of cancer screening and genotyping, and to enable targeted therapies in resource-limited settings.
