Login In
2024 Volume 43 Issue 2
2024, 43(2): 100203
doi: 10.1016/j.cjsc.2023.100203
Abstract:
Lithium metal batteries (LMBs) represent a promising frontier in energy storage technology, offering high energy density but facing significant challenges. In this work, we address the critical challenge of lithium dendrite formation in LMBs, a key barrier to their efficiency and safety. Focusing on the potential of electrolyte additives, specifically lithium nitrate, to inhibit dendritic growth, we employ advanced multi-scale simulation techniques to explore the formation and properties of the solid electrolyte interphase (SEI) on the anode surface. Our study introduces a novel hybrid simulation methodology, HAIR (Hybrid ab initio and Reactive force field Molecular Dynamics), which combines ab initio molecular dynamics (AIMD) and reactive force field molecular dynamics (RMD). This approach allows for a more precise and reliable examination of the interaction mechanisms of nitrate additives within LMBs. Our findings demonstrate that lithium nitrate contributes to the formation of a stable and fast ionic conductor interface, effectively suppressing dendrite growth. These insights not only advance our understanding of dendrite formation and mitigation strategies in lithium metal batteries, but also highlight the efficacy of HAIR as a pioneering tool for simulating complex chemical interactions in battery materials, offering significant implications for the broader field of energy storage technology.
Lithium metal batteries (LMBs) represent a promising frontier in energy storage technology, offering high energy density but facing significant challenges. In this work, we address the critical challenge of lithium dendrite formation in LMBs, a key barrier to their efficiency and safety. Focusing on the potential of electrolyte additives, specifically lithium nitrate, to inhibit dendritic growth, we employ advanced multi-scale simulation techniques to explore the formation and properties of the solid electrolyte interphase (SEI) on the anode surface. Our study introduces a novel hybrid simulation methodology, HAIR (Hybrid ab initio and Reactive force field Molecular Dynamics), which combines ab initio molecular dynamics (AIMD) and reactive force field molecular dynamics (RMD). This approach allows for a more precise and reliable examination of the interaction mechanisms of nitrate additives within LMBs. Our findings demonstrate that lithium nitrate contributes to the formation of a stable and fast ionic conductor interface, effectively suppressing dendrite growth. These insights not only advance our understanding of dendrite formation and mitigation strategies in lithium metal batteries, but also highlight the efficacy of HAIR as a pioneering tool for simulating complex chemical interactions in battery materials, offering significant implications for the broader field of energy storage technology.
2024, 43(2): 100206
doi: 10.1016/j.cjsc.2023.100206
Abstract:
With the continuous depletion of traditional energy sources, the development of sustainable energy sources has become one of the important tasks today. A two-step synthesis method was employed to construct Ni3S2/ZrCoFe-LDH@NF heterostructured electrocatalysts on nickel foam (NF) in situ. X-ray diffractometer, scanning electron microscope, transmission electron microscope, and X-ray electron spectroscopy were employed to characterize the Ni3S2/ZrCoFe-LDH@NF heterostructure, and the hydrogen-extraction reaction (HER), oxygen-extraction reaction (OER) and total hydrolysis properties of this electrocatalyst were tested in 1 mol·L−1 KOH electrolyte. It is shown that Ni3S2/ZrCoFe-LDH@NF is a lamellar stacked heterostructure with an overpotential of 330 mV and a Tafel slope of 90.9 mV·dec−1 at a current density of 100 mA·cm−2 in the OER reaction and 159.2 mV at a current density of 10 mA·cm−2 in the HER reaction. The Tafel slope is 96 mV·dec−1, and the catalyst exhibits good structural stability in the 100 h total hydrolysis stability test. The successful construction of this heterostructured electrocatalyst provides a good idea and research basis for the subsequent heterojunction and its application in electrocatalysis.
With the continuous depletion of traditional energy sources, the development of sustainable energy sources has become one of the important tasks today. A two-step synthesis method was employed to construct Ni3S2/ZrCoFe-LDH@NF heterostructured electrocatalysts on nickel foam (NF) in situ. X-ray diffractometer, scanning electron microscope, transmission electron microscope, and X-ray electron spectroscopy were employed to characterize the Ni3S2/ZrCoFe-LDH@NF heterostructure, and the hydrogen-extraction reaction (HER), oxygen-extraction reaction (OER) and total hydrolysis properties of this electrocatalyst were tested in 1 mol·L−1 KOH electrolyte. It is shown that Ni3S2/ZrCoFe-LDH@NF is a lamellar stacked heterostructure with an overpotential of 330 mV and a Tafel slope of 90.9 mV·dec−1 at a current density of 100 mA·cm−2 in the OER reaction and 159.2 mV at a current density of 10 mA·cm−2 in the HER reaction. The Tafel slope is 96 mV·dec−1, and the catalyst exhibits good structural stability in the 100 h total hydrolysis stability test. The successful construction of this heterostructured electrocatalyst provides a good idea and research basis for the subsequent heterojunction and its application in electrocatalysis.
2024, 43(2): 100207
doi: 10.1016/j.cjsc.2023.100207
Abstract:
Copper tungstate (CuWO4) is a promising photoanode for photoelectrochemical (PEC) water splitting due to its appropriate energy band position and broad light absorption range. However, the inherent unfilled 3d atomic orbital of Cu acts as a natural electron-hole recombination site, significantly constraining the PEC performance of CuWO4. Herein, Cs atoms with complete atomic orbitals are doped into CuWO4 in order to obtain better bulk charge separation capability. As a result, the photocurrent of Cs@CuWO4 increases from 0.57 to 0.99 mA cm−2 compared to CuWO4 at 1.23 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination, as well as the bulk charge transfer efficiencies rising from 13.5% to 19.3%. In addition, density of states (DOS) calculations further prove that the introduction of Cs atoms effectively suppresses the contribution of Cu 3d orbitals at the Fermi level. This work offers a valuable reference for the advancement of CuWO4 as the next-generation PEC photoanode material.
Copper tungstate (CuWO4) is a promising photoanode for photoelectrochemical (PEC) water splitting due to its appropriate energy band position and broad light absorption range. However, the inherent unfilled 3d atomic orbital of Cu acts as a natural electron-hole recombination site, significantly constraining the PEC performance of CuWO4. Herein, Cs atoms with complete atomic orbitals are doped into CuWO4 in order to obtain better bulk charge separation capability. As a result, the photocurrent of Cs@CuWO4 increases from 0.57 to 0.99 mA cm−2 compared to CuWO4 at 1.23 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination, as well as the bulk charge transfer efficiencies rising from 13.5% to 19.3%. In addition, density of states (DOS) calculations further prove that the introduction of Cs atoms effectively suppresses the contribution of Cu 3d orbitals at the Fermi level. This work offers a valuable reference for the advancement of CuWO4 as the next-generation PEC photoanode material.
2024, 43(2): 100208
doi: 10.1016/j.cjsc.2023.100208
Abstract:
Coal gangue (CG), a solid waste from coal mining and processing, has raised concerns about its environmental impact. Graphitic carbon nitride (g-C3N4) is promising for photocatalytic decomposition of organic pollutants, but its performance is hampered by its inherent defects. In this study, the compound of coal gangue and g-C3N4 was formed by in-situ loading g-C3N4 on the surface of coal gangue. After recombination, the morphology of g-C3N4 changes from block structure to tremella nanosheet. This change not only increases the specific surface area of g-C3N4, but also broadens the light absorption spectrum of g-C3N4. Compared with original g-C3N4, the photocurrent of the complex in visible light is increased twice, and the tetracycline (TC) degradation rate is 2.1 times faster. The structure, optical properties, band structure, morphology and charge transfer mechanism of the composite were analyzed by a series of characterization techniques. It is found that coal gangue can promote the space charge transfer and separation of g-C3N4, and the cyclic test compound has good activity stability. In this paper, a strategy of comprehensive utilization of coal gangue is proposed, which can not only reduce the environmental risk of coal gangue, but also provide carbon nitride (CN) based photocatalytic materials with superior photocatalytic properties.
Coal gangue (CG), a solid waste from coal mining and processing, has raised concerns about its environmental impact. Graphitic carbon nitride (g-C3N4) is promising for photocatalytic decomposition of organic pollutants, but its performance is hampered by its inherent defects. In this study, the compound of coal gangue and g-C3N4 was formed by in-situ loading g-C3N4 on the surface of coal gangue. After recombination, the morphology of g-C3N4 changes from block structure to tremella nanosheet. This change not only increases the specific surface area of g-C3N4, but also broadens the light absorption spectrum of g-C3N4. Compared with original g-C3N4, the photocurrent of the complex in visible light is increased twice, and the tetracycline (TC) degradation rate is 2.1 times faster. The structure, optical properties, band structure, morphology and charge transfer mechanism of the composite were analyzed by a series of characterization techniques. It is found that coal gangue can promote the space charge transfer and separation of g-C3N4, and the cyclic test compound has good activity stability. In this paper, a strategy of comprehensive utilization of coal gangue is proposed, which can not only reduce the environmental risk of coal gangue, but also provide carbon nitride (CN) based photocatalytic materials with superior photocatalytic properties.
2024, 43(2): 100211
doi: 10.1016/j.cjsc.2023.100211
Abstract:
In conclusion, employing the isoreticular series of UZr-X as model systems, the UZr–NH2 exhibits the highest activity, achieving a yield of 81% after 10 h of reaction. This performance surpasses that of aminomodified MTi-NH2 and MIn-NH2, which can be attributed to the optimal electronegativity of Zr4+. DRFTIR analyses confirmed the generation of activated CO2– species during the reaction. Concurrently, the formation of NH2–CO2 and N–CO2 coordination models has been validated through theoretical calculations. Thus, in conclusion, the amino substituent and exposed zirconium sites are the crucial active sites for this reaction. In essence, the interplay between the Lewis acid/base active site and the adsorption-coordination effect culminates in the superior performance observed in CO2 cycloaddition.
In conclusion, employing the isoreticular series of UZr-X as model systems, the UZr–NH2 exhibits the highest activity, achieving a yield of 81% after 10 h of reaction. This performance surpasses that of aminomodified MTi-NH2 and MIn-NH2, which can be attributed to the optimal electronegativity of Zr4+. DRFTIR analyses confirmed the generation of activated CO2– species during the reaction. Concurrently, the formation of NH2–CO2 and N–CO2 coordination models has been validated through theoretical calculations. Thus, in conclusion, the amino substituent and exposed zirconium sites are the crucial active sites for this reaction. In essence, the interplay between the Lewis acid/base active site and the adsorption-coordination effect culminates in the superior performance observed in CO2 cycloaddition.
2024, 43(2): 100214
doi: 10.1016/j.cjsc.2024.100214
Abstract:
In the midst of the rapid advancement of photocatalysis, direct Z-scheme heterojunction photocatalysts have emerged as a powerful solution to address environmental challenges and the looming energy crisis. The precise engineering of direct Z-scheme heterojunction photocatalysts proves highly beneficial in optimizing their electronic structure, ultimately enhancing their photocatalytic performance. Notably, graphitic carbon nitride (g-C3N4) has recently gained recognition as a leading candidate for the creation of direct Z-scheme heterojunctions, owing to its favorable attributes such as a moderate band-gap (2.7 eV), high reduction potential and abundant active sites. In this review, we offer a concise overview of the fundamental principles and recent advancements in g-C3N4-based direct Z-scheme photocatalytic systems. Furthermore, we delve into the various practical applications of g-C3N4-based direct Z-scheme photocatalysts, specifically in the realms of energy conversion and environmental remediation. These applications include the removal of contaminant pollutants through photocatalytic degradation, water splitting (comprising H2-generation, O2-evolution, and overall water splitting), and CO2 reduction. Additionally, we present comprehensive characterization methods and strategies aimed at further enhancing the photocatalytic activity of g-C3N4-based direct Z-scheme photocatalytic systems. To conclude, this review offers summarizing insights and a brief discussion on future challenges and prospects pertaining to g-C3N4-based direct Z-scheme photocatalysts. We believe that this review will inspire continued exploration and foster a deeper understanding of the groundbreaking possibilities within photocatalytic activity. This also provides valuable guidance for the design and construction of innovative direct Z-scheme photocatalysts.
In the midst of the rapid advancement of photocatalysis, direct Z-scheme heterojunction photocatalysts have emerged as a powerful solution to address environmental challenges and the looming energy crisis. The precise engineering of direct Z-scheme heterojunction photocatalysts proves highly beneficial in optimizing their electronic structure, ultimately enhancing their photocatalytic performance. Notably, graphitic carbon nitride (g-C3N4) has recently gained recognition as a leading candidate for the creation of direct Z-scheme heterojunctions, owing to its favorable attributes such as a moderate band-gap (2.7 eV), high reduction potential and abundant active sites. In this review, we offer a concise overview of the fundamental principles and recent advancements in g-C3N4-based direct Z-scheme photocatalytic systems. Furthermore, we delve into the various practical applications of g-C3N4-based direct Z-scheme photocatalysts, specifically in the realms of energy conversion and environmental remediation. These applications include the removal of contaminant pollutants through photocatalytic degradation, water splitting (comprising H2-generation, O2-evolution, and overall water splitting), and CO2 reduction. Additionally, we present comprehensive characterization methods and strategies aimed at further enhancing the photocatalytic activity of g-C3N4-based direct Z-scheme photocatalytic systems. To conclude, this review offers summarizing insights and a brief discussion on future challenges and prospects pertaining to g-C3N4-based direct Z-scheme photocatalysts. We believe that this review will inspire continued exploration and foster a deeper understanding of the groundbreaking possibilities within photocatalytic activity. This also provides valuable guidance for the design and construction of innovative direct Z-scheme photocatalysts.
Boosting hydrogen production of ammonia decomposition via the construction of metal-oxide interfaces
2024, 43(2): 100236
doi: 10.1016/j.cjsc.2024.100236
Abstract:
The ammonia decomposition for the production of carbon-free hydrogen has triggered great attention yet still remains challenging due to its sluggish kinetics, posting the importance of precise design of efficient catalysts for ammonia decomposition under low temperatures. Constructing the metal-support interaction and interface is one of the most important strategies for promoting catalysts. In this work, by coating ceria onto the Ni nanoparticles (NPs), we discover that the Ni–CeO2 interfaces create an exceptional effect to enhance the catalytic decomposition of ammonia by over 10 folds, compared with the pristine Ni. The kinetic analysis demonstrates that the recombinative N2 desorption is the rate-determining step (RDS) and the Ni–CeO2 interface greatly increases the RDS. Based on these understandings, a strategy to fabricate the Ni/CeO2 catalyst with abundant Ni–Ce–O interfaces via one-pot sol-gel method was employed (hereafter denoted to s–Ni/CeO2). The s–Ni/CeO2 catalyst shows a high activity for ammonia decomposition, achieving a H2 formation rate of 10.5 mmol gcat−1 min−1 at 550 °C. Combined with a series of characterizations, the relationship between the catalyst structure and the performance was investigated for further understanding the effect of metal-oxide interfaces.
The ammonia decomposition for the production of carbon-free hydrogen has triggered great attention yet still remains challenging due to its sluggish kinetics, posting the importance of precise design of efficient catalysts for ammonia decomposition under low temperatures. Constructing the metal-support interaction and interface is one of the most important strategies for promoting catalysts. In this work, by coating ceria onto the Ni nanoparticles (NPs), we discover that the Ni–CeO2 interfaces create an exceptional effect to enhance the catalytic decomposition of ammonia by over 10 folds, compared with the pristine Ni. The kinetic analysis demonstrates that the recombinative N2 desorption is the rate-determining step (RDS) and the Ni–CeO2 interface greatly increases the RDS. Based on these understandings, a strategy to fabricate the Ni/CeO2 catalyst with abundant Ni–Ce–O interfaces via one-pot sol-gel method was employed (hereafter denoted to s–Ni/CeO2). The s–Ni/CeO2 catalyst shows a high activity for ammonia decomposition, achieving a H2 formation rate of 10.5 mmol gcat−1 min−1 at 550 °C. Combined with a series of characterizations, the relationship between the catalyst structure and the performance was investigated for further understanding the effect of metal-oxide interfaces.
2024, 43(2): 100238
doi: 10.1016/j.cjsc.2024.100238
Abstract:
In summary, the 2D porous material with unique pore configuration, ultrathin structure, abundant mesopores and appealing surface properties, is one of the most promising candidates for obtaining efficient functional nanomaterials for practical applications. The reported monolayer mesoporous nanosheets consisting of “U-shaped” mesopore units with a unique surface asymmetry can exhibit a high demulsification efficiency and stability. The formation mechanism and the structure activity relationship of such 2D mesoporous Janus nanosheet were also revealed. Nevertheless, the component obtained by this dual-emulsion directed monomicelle assembly was only for organosilica, and it was hard to extend to other components, limiting their potential applications. So, it is significant to improve the versatility of this synthetic strategy. Overall, the current work contributes new insights to the invention of brand-new mesoporous materials with hierarchical structures, new pore configuration and surface properties, which can attract a broad readership in chemistry, materials science, and biomedical engineering
In summary, the 2D porous material with unique pore configuration, ultrathin structure, abundant mesopores and appealing surface properties, is one of the most promising candidates for obtaining efficient functional nanomaterials for practical applications. The reported monolayer mesoporous nanosheets consisting of “U-shaped” mesopore units with a unique surface asymmetry can exhibit a high demulsification efficiency and stability. The formation mechanism and the structure activity relationship of such 2D mesoporous Janus nanosheet were also revealed. Nevertheless, the component obtained by this dual-emulsion directed monomicelle assembly was only for organosilica, and it was hard to extend to other components, limiting their potential applications. So, it is significant to improve the versatility of this synthetic strategy. Overall, the current work contributes new insights to the invention of brand-new mesoporous materials with hierarchical structures, new pore configuration and surface properties, which can attract a broad readership in chemistry, materials science, and biomedical engineering
2024, 43(2): 100241
doi: 10.1016/j.cjsc.2024.100241
Abstract:
One of the exciting applications of CO2-induced magnetism changes is in the field of gas sensing. Sensors that can detect the presence and concentration of CO2 are crucial for environmental monitoring, industrial processes, and even healthcare. Magnetic materials that change their properties in the presence of CO2 could lead to the development of highly sensitive and selective gas sensors. In addition, it opens the door to a range of novel functional devices. For instance, such materials could be used in information storage systems, where data could be written or erased in response to CO2 exposure. Finally, it is also noteworthy that the use of CO2 to alter magnetism also aligns with global environmental goals, which may contribute to the efforts towards achieving carbon neutrality and managing green-house gas emissions.
One of the exciting applications of CO2-induced magnetism changes is in the field of gas sensing. Sensors that can detect the presence and concentration of CO2 are crucial for environmental monitoring, industrial processes, and even healthcare. Magnetic materials that change their properties in the presence of CO2 could lead to the development of highly sensitive and selective gas sensors. In addition, it opens the door to a range of novel functional devices. For instance, such materials could be used in information storage systems, where data could be written or erased in response to CO2 exposure. Finally, it is also noteworthy that the use of CO2 to alter magnetism also aligns with global environmental goals, which may contribute to the efforts towards achieving carbon neutrality and managing green-house gas emissions.
2024, 43(2): 100242
doi: 10.1016/j.cjsc.2024.100242
Abstract:
In conclusion, the rod-like HP/CoP2 composite synthesized by CVD and subsequent template etching process has demonstrated to be an effective visible light driven photocatalyst for HER from pure water splitting for the first time. Remarkably, the optimized HP/CoP2 exhibited an excellent photocatalytic HER rate of 13.1 μmol h-1, which is about 4 times higher than that of HP/Pt under identical experimental conditions. The experimental results reveal that CoP2 served as nucleation sites for the growth of one-dimensional HP rods, establishing a close interfacial contact through Co–P bonds between HP and CoP2 to facilitate charge-carrier separation and migration. Additionally, the decoration of CoP2 on HP acted as cocatalyst further promoting the HER kinetics. Consequently, a significantly enhanced photocatalytic hydrogen production performance was achieved in the optimized HP/CoP2 composite. This finding introduces a novel approach in the design of superior phosphorus-based photocatalysts for water splitting.
In conclusion, the rod-like HP/CoP2 composite synthesized by CVD and subsequent template etching process has demonstrated to be an effective visible light driven photocatalyst for HER from pure water splitting for the first time. Remarkably, the optimized HP/CoP2 exhibited an excellent photocatalytic HER rate of 13.1 μmol h-1, which is about 4 times higher than that of HP/Pt under identical experimental conditions. The experimental results reveal that CoP2 served as nucleation sites for the growth of one-dimensional HP rods, establishing a close interfacial contact through Co–P bonds between HP and CoP2 to facilitate charge-carrier separation and migration. Additionally, the decoration of CoP2 on HP acted as cocatalyst further promoting the HER kinetics. Consequently, a significantly enhanced photocatalytic hydrogen production performance was achieved in the optimized HP/CoP2 composite. This finding introduces a novel approach in the design of superior phosphorus-based photocatalysts for water splitting.
2024, 43(2): 100243
doi: 10.1016/j.cjsc.2024.100243
Abstract:
Highly active and low-cost oxygen evolution reaction (OER) catalytic electrodes are extremely essential for exploration of green hydrogen via water splitting. Herein, an advanced Fe–Ni–F electrocatalyst is fabricated by a facile annealing strategy using ammonium fluoride, of which the structure feature is unveiled by XRD, FESEM, TEM, EDS, BET, and XPS measurements. The as-prepared Fe–Ni–F addresses a low overpotential of 277 mV and a small Tafel slope of 49 mV dec−1 at a current density of 10 mA cm−2, significantly outperforming other control samples as well as the state-of-the-art RuO2. The advanced nature of our Fe–Ni–F catalyst could also be further evidenced from the robust stability in KOH alkaline solution, showing as 5.41% degradation after 24 h continuous working. Upon analysis, it suggests that the decent catalytic activity should be attributed to the formed bimetallic (oxy)hydroxides because of the introduction of fluoride and the synergistic effect of iron and nickel towards oxygen generation. This work represents the potential of Fe- and/or Ni-based fluoride as efficient catalyst for low-energy consumption oxygen generation.
Highly active and low-cost oxygen evolution reaction (OER) catalytic electrodes are extremely essential for exploration of green hydrogen via water splitting. Herein, an advanced Fe–Ni–F electrocatalyst is fabricated by a facile annealing strategy using ammonium fluoride, of which the structure feature is unveiled by XRD, FESEM, TEM, EDS, BET, and XPS measurements. The as-prepared Fe–Ni–F addresses a low overpotential of 277 mV and a small Tafel slope of 49 mV dec−1 at a current density of 10 mA cm−2, significantly outperforming other control samples as well as the state-of-the-art RuO2. The advanced nature of our Fe–Ni–F catalyst could also be further evidenced from the robust stability in KOH alkaline solution, showing as 5.41% degradation after 24 h continuous working. Upon analysis, it suggests that the decent catalytic activity should be attributed to the formed bimetallic (oxy)hydroxides because of the introduction of fluoride and the synergistic effect of iron and nickel towards oxygen generation. This work represents the potential of Fe- and/or Ni-based fluoride as efficient catalyst for low-energy consumption oxygen generation.
2024, 43(2): 100246
doi: 10.1016/j.cjsc.2024.100246
Abstract:
This study provides a novel and promising research direction for the high efficient and high value-added electrocatalytic conversion of biomass coupled with low cost hydrogen production, which has important theoretical and practical significance for promoting the development of hydrogen production technology by proton exchange membrane electrolysis and catalytic conversion of high value-added biomass. In short, we hope that solar photocatalysis can be used in the future to replace thermal catalytic biomass oxidation to formic acid, so as to reduce energy consumption and environmental pollution to a greater extent.
This study provides a novel and promising research direction for the high efficient and high value-added electrocatalytic conversion of biomass coupled with low cost hydrogen production, which has important theoretical and practical significance for promoting the development of hydrogen production technology by proton exchange membrane electrolysis and catalytic conversion of high value-added biomass. In short, we hope that solar photocatalysis can be used in the future to replace thermal catalytic biomass oxidation to formic acid, so as to reduce energy consumption and environmental pollution to a greater extent.
