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2022 Volume 41 Issue 5
2022, 41(5): 220500
doi: 10.14102/j.cnki.0254-5861.2022-0075
Abstract:
Porous crystalline metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are promising platforms for electrocatalytic reduction of CO2 (CO2RR) due to their large CO2 adsorption uptakes and periodically arranged single active sites. However, the applications in CO2RR of the traditional MOFs and COFs are greatly limited by their low electron conductivity. In recent years, numerous types of MOFs and COFs with high intrinsic conductivity have been rationally designed and successfully constructed, and some of them have been applied in CO2RR. In this review, the applications of conductive MOFs and COFs in CO2RR have been summarized. The conductive MOFs and COFs can be categorized according to the methods, in which the conductivity is enhanced, such as constructing fully π-conjugated backbones, donor-acceptor heterojunction, enhancing the π-π stacking interactions between organic moieties and/or the introduction of guest molecules.
Porous crystalline metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are promising platforms for electrocatalytic reduction of CO2 (CO2RR) due to their large CO2 adsorption uptakes and periodically arranged single active sites. However, the applications in CO2RR of the traditional MOFs and COFs are greatly limited by their low electron conductivity. In recent years, numerous types of MOFs and COFs with high intrinsic conductivity have been rationally designed and successfully constructed, and some of them have been applied in CO2RR. In this review, the applications of conductive MOFs and COFs in CO2RR have been summarized. The conductive MOFs and COFs can be categorized according to the methods, in which the conductivity is enhanced, such as constructing fully π-conjugated backbones, donor-acceptor heterojunction, enhancing the π-π stacking interactions between organic moieties and/or the introduction of guest molecules.
2022, 41(5): 220501
doi: 10.14102/j.cnki.0254-5861.2022-0106
Abstract:
Hydrogen production from water splitting is a clean and sustainable hydrogen production route to alleviate the current energy crisis. However, factors such as energy conversion efficiency, cost-effectiveness, and social benefit limit their industrial application. Therefore, the development of advanced water splitting technologies using clean and renewable energy has become an important research goal of the world. Converting endless solar energy into hydrogen energy directly or indirectly is an effective way to reduce the energy input of hydrogen production. This review focuses on the latest advances in the coupling design of renewable energy supply devices and catalytic electrodes in hydrogen production systems. We not only review the single hydrogen production system based on photochemical, photoelectrochemical, photovoltaic, thermoelectric, pyroelectric, and piezoelectric devices, but also discuss the complex systems of the multiple devices. The structural design of energy supply devices and catalytic electrodes and the study of hydrogen production performance in different systems will be critically discussed in this work. Finally, current challenges and future perspectives of advanced technologies for sunlight-electricity-hydrogen nexus are also presented. It is hoped that this review will provide a timely reference for advancing the development of sunlight-electricity-hydrogen nexus and thus achieve the goal of sustainable production of green hydrogen.
Hydrogen production from water splitting is a clean and sustainable hydrogen production route to alleviate the current energy crisis. However, factors such as energy conversion efficiency, cost-effectiveness, and social benefit limit their industrial application. Therefore, the development of advanced water splitting technologies using clean and renewable energy has become an important research goal of the world. Converting endless solar energy into hydrogen energy directly or indirectly is an effective way to reduce the energy input of hydrogen production. This review focuses on the latest advances in the coupling design of renewable energy supply devices and catalytic electrodes in hydrogen production systems. We not only review the single hydrogen production system based on photochemical, photoelectrochemical, photovoltaic, thermoelectric, pyroelectric, and piezoelectric devices, but also discuss the complex systems of the multiple devices. The structural design of energy supply devices and catalytic electrodes and the study of hydrogen production performance in different systems will be critically discussed in this work. Finally, current challenges and future perspectives of advanced technologies for sunlight-electricity-hydrogen nexus are also presented. It is hoped that this review will provide a timely reference for advancing the development of sunlight-electricity-hydrogen nexus and thus achieve the goal of sustainable production of green hydrogen.
2022, 41(5): 220503
doi: 10.14102/j.cnki.0254-5861.2022-0044
Abstract:
Metal sulfides have been regarded as promising anodes for potassium-ion batteries (PIBs) due to their high theoretical capacities, while the performance is limited by their intrinsic poor conductivity and large volume fluctuation during the insertion/extraction of large potassium ion. Herein, the battery performance of iron sulfide anode is significantly enhanced through yolk-shell (Y-S) structure design and nickel doping, aiming to realize good structure stability and superior electron/ion transportation. For potassium storage, as-prepared Y-S Ni-FeS2@C shows excellent cyclic performance and sustains high capacities of 328 mA h g-1 after 100 cycles at 0.2 A g-1 and 226 mA h g-1 after 1000 cycles at 1 A g-1. Especially, it displays a superior rate capacity of 200 mA h g-1 at 20 A g-1, higher than that of Y-S FeS2@C and most as-reported metal sulfide anodes for PIBs. The experimental analysis and theoretical calculation illuminate the effect of Ni-doping on decreasing the particle size of iron sulfide and enhancing the ion/electron transport ability, thus accounting for the exceptional rate capability of Y-S Ni-FeS2@C composite.
Metal sulfides have been regarded as promising anodes for potassium-ion batteries (PIBs) due to their high theoretical capacities, while the performance is limited by their intrinsic poor conductivity and large volume fluctuation during the insertion/extraction of large potassium ion. Herein, the battery performance of iron sulfide anode is significantly enhanced through yolk-shell (Y-S) structure design and nickel doping, aiming to realize good structure stability and superior electron/ion transportation. For potassium storage, as-prepared Y-S Ni-FeS2@C shows excellent cyclic performance and sustains high capacities of 328 mA h g-1 after 100 cycles at 0.2 A g-1 and 226 mA h g-1 after 1000 cycles at 1 A g-1. Especially, it displays a superior rate capacity of 200 mA h g-1 at 20 A g-1, higher than that of Y-S FeS2@C and most as-reported metal sulfide anodes for PIBs. The experimental analysis and theoretical calculation illuminate the effect of Ni-doping on decreasing the particle size of iron sulfide and enhancing the ion/electron transport ability, thus accounting for the exceptional rate capability of Y-S Ni-FeS2@C composite.
2022, 41(5): 220503
doi: 10.14102/j.cnki.0254-5861.2022-0061
Abstract:
Here we report an example of a general strategy for the immobilization of various different photochromic spiropyran molecules on eco-friendly cheap nanomatrix. The spiropyrans are encapsulated in calcium salt oligomers-based gels by centrifugation, forming an inorganic oligomer-based gelatinous photoswitchable hybrid material. Ca2+ is also used to regulate the optical properties of spiropyrans through chelation. The oligomer-based gel can not only provide the space required for photoisomerization, but also reduce the interference of the surrounding environment on the photochromic properties. Moreover, a practical paper-based and colloidal flexible substrate platform is constructed for the removal and naked-eye detection of liquid and gaseous hydrazine at room temperature based on the reactivity of the formyl group on spiropyrans loaded in Ca3(PO4)2 oligomers. This general strategy can be used for other inorganic oligomer-based molecular switches and sensing systems.
Here we report an example of a general strategy for the immobilization of various different photochromic spiropyran molecules on eco-friendly cheap nanomatrix. The spiropyrans are encapsulated in calcium salt oligomers-based gels by centrifugation, forming an inorganic oligomer-based gelatinous photoswitchable hybrid material. Ca2+ is also used to regulate the optical properties of spiropyrans through chelation. The oligomer-based gel can not only provide the space required for photoisomerization, but also reduce the interference of the surrounding environment on the photochromic properties. Moreover, a practical paper-based and colloidal flexible substrate platform is constructed for the removal and naked-eye detection of liquid and gaseous hydrazine at room temperature based on the reactivity of the formyl group on spiropyrans loaded in Ca3(PO4)2 oligomers. This general strategy can be used for other inorganic oligomer-based molecular switches and sensing systems.
2022, 41(5): 220504
doi: 10.14102/j.cnki.0254-5861.2022-0067
Abstract:
Succinonitrile (SN) based solid-state electrolytes (SSEs) have potential applications in lithium (Li) batteries due to their ease of preparation and high ionic conductivity at room temperature. Here, a novel SSE consisting of poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP), poly(methyl methacrylate) (PMMA) and Li1.3Al0.3Ti1.7(PO4)3 with SN is fabricated, where PMMA is added to serve as a polymer matrix for better wettability of SN. Due to the addition of PMMA, improved room-temperature ionic conductivity of the SSE is resulted. More importantly, better interfacial contact as well as more stable solid electrolyte interphase (SEI) layer between SSE and Li anode can be also obtained. As a result, homogeneous and dendrite-free Li plating can be achieved for over 1000 h in Li symmetric cells. When coupled with LiNi0.5Mn0.3Co0.2O2 cathode and Li anode, the proposed SSE delivers excellent cycling stability and rate capability in full-cells. By implementing SSEs with a polymeric wetting agent, this work provides fresh perspectives on stabilizing the interface between SSEs and Li metal anodes.
Succinonitrile (SN) based solid-state electrolytes (SSEs) have potential applications in lithium (Li) batteries due to their ease of preparation and high ionic conductivity at room temperature. Here, a novel SSE consisting of poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP), poly(methyl methacrylate) (PMMA) and Li1.3Al0.3Ti1.7(PO4)3 with SN is fabricated, where PMMA is added to serve as a polymer matrix for better wettability of SN. Due to the addition of PMMA, improved room-temperature ionic conductivity of the SSE is resulted. More importantly, better interfacial contact as well as more stable solid electrolyte interphase (SEI) layer between SSE and Li anode can be also obtained. As a result, homogeneous and dendrite-free Li plating can be achieved for over 1000 h in Li symmetric cells. When coupled with LiNi0.5Mn0.3Co0.2O2 cathode and Li anode, the proposed SSE delivers excellent cycling stability and rate capability in full-cells. By implementing SSEs with a polymeric wetting agent, this work provides fresh perspectives on stabilizing the interface between SSEs and Li metal anodes.
2022, 41(5): 220505
doi: 10.14102/j.cnki.0254-5861.2022-0070
Abstract:
To conquer inherently low conductivity, volume swelling, and labile solid electrolyte interphase (SEI) films of Si anode in lithium ion battery (LIBs), it is widely accepted that appropriate structure design of Si-C hybrids performs effectively, especially for nanosize Si particles. Herein, inspired by the sturdy construction of high-rise buildings, a mansion-like 3D structured Si@SiO2/PBC/RGO (SSPBG) with separated rooms is developed based on 0D core-shell Si@SiO2, 1D pyrolytic bacterial cellulose (PBC) and 2D reduced graphene oxide (RGO). Therefore, these hierarchical protectors operate synergistically to inhibit the inevitable volume changes during electrochemical process. Specifically, tightly coated SiO2 shell as the first protective layer could buffer the volume expansion and reduce detrimental pulverization of Si NPs. Furthermore, flexible spring-like PBC and ultra-fine RGO sheets perform as securer barriers and skeleton which will counteract the microstructure strain and accelerate electron transfer at the same time. Remarkably, the self-supporting electrode realizes a distinguished performance of 901 mAh g-1 at 2 A g-1 for 500 cycles. When matched with LiFePO4 cathodes, high stability of more than 100 cycles has been realized for the full batteries.
To conquer inherently low conductivity, volume swelling, and labile solid electrolyte interphase (SEI) films of Si anode in lithium ion battery (LIBs), it is widely accepted that appropriate structure design of Si-C hybrids performs effectively, especially for nanosize Si particles. Herein, inspired by the sturdy construction of high-rise buildings, a mansion-like 3D structured Si@SiO2/PBC/RGO (SSPBG) with separated rooms is developed based on 0D core-shell Si@SiO2, 1D pyrolytic bacterial cellulose (PBC) and 2D reduced graphene oxide (RGO). Therefore, these hierarchical protectors operate synergistically to inhibit the inevitable volume changes during electrochemical process. Specifically, tightly coated SiO2 shell as the first protective layer could buffer the volume expansion and reduce detrimental pulverization of Si NPs. Furthermore, flexible spring-like PBC and ultra-fine RGO sheets perform as securer barriers and skeleton which will counteract the microstructure strain and accelerate electron transfer at the same time. Remarkably, the self-supporting electrode realizes a distinguished performance of 901 mAh g-1 at 2 A g-1 for 500 cycles. When matched with LiFePO4 cathodes, high stability of more than 100 cycles has been realized for the full batteries.
2022, 41(5): 220506
doi: 10.14102/j.cnki.0254-5861.2022-0074
Abstract:
2, 5-dihydroxymethylfuran (DHMF), obtained from 5-hydroxymethylfurfural (HMF) by electrochemical method, is a promising building block for polymers. However, one challenge of this process is to reduce initial potential and improve catalytic selectivity. In this work, the PdCu bimetallic catalyst is prepared with an onset potential of-0.05 VRHE and a selectivity of 99%. Compared with the single Cu electrocatalyst, the adsorption of HMF and proton is improved by introducing of Pd, which is demonstrated by the electrochemical results and hydrogen production rate. This work provides an effective strategy to improve the selectivity of Cu-based electrocatalyst and builds a relationship between the adsorption capacity and the electrocatalytic performance.
2, 5-dihydroxymethylfuran (DHMF), obtained from 5-hydroxymethylfurfural (HMF) by electrochemical method, is a promising building block for polymers. However, one challenge of this process is to reduce initial potential and improve catalytic selectivity. In this work, the PdCu bimetallic catalyst is prepared with an onset potential of-0.05 VRHE and a selectivity of 99%. Compared with the single Cu electrocatalyst, the adsorption of HMF and proton is improved by introducing of Pd, which is demonstrated by the electrochemical results and hydrogen production rate. This work provides an effective strategy to improve the selectivity of Cu-based electrocatalyst and builds a relationship between the adsorption capacity and the electrocatalytic performance.
2022, 41(5): 220507
doi: 10.14102/j.cnki.0254-5861.2022-0088
Abstract:
Mn2+-doped lead halide perovskites either in 3D or 2D have been extensively explored due to their rich energy-transfer behaviors. While their application on LED is still lagging behind in comparison to non-doped 3D perovskite due to inferior film-formation and low luminescent efficiency. Here we report an in-situ-formed Mn2+ doped 2D perovskite nanocrystal (NCs) film by introducing quaternary phosphonium salt during the crystallizing process. The as-formed film shows improved luminescent efficiency with emission peaked at 600 nm and photoluminescence quantum yield (PLQY) of as high as 73.37%, which is about 1.3 times higher than that of pristine film. Further characterizations confirm the enhanced confinement effect from smaller size particle is responsible for the improved luminescent efficiency. The perovskite LEDs based on pristine and phosphonium passivated thin films were fabricated, and a great improvement in the external quantum efficiency of these LEDs (from 0.0017% to 0.12%) is observed due to the improved morphology and enhanced luminescent efficiency.
Mn2+-doped lead halide perovskites either in 3D or 2D have been extensively explored due to their rich energy-transfer behaviors. While their application on LED is still lagging behind in comparison to non-doped 3D perovskite due to inferior film-formation and low luminescent efficiency. Here we report an in-situ-formed Mn2+ doped 2D perovskite nanocrystal (NCs) film by introducing quaternary phosphonium salt during the crystallizing process. The as-formed film shows improved luminescent efficiency with emission peaked at 600 nm and photoluminescence quantum yield (PLQY) of as high as 73.37%, which is about 1.3 times higher than that of pristine film. Further characterizations confirm the enhanced confinement effect from smaller size particle is responsible for the improved luminescent efficiency. The perovskite LEDs based on pristine and phosphonium passivated thin films were fabricated, and a great improvement in the external quantum efficiency of these LEDs (from 0.0017% to 0.12%) is observed due to the improved morphology and enhanced luminescent efficiency.
2022, 41(5): 220507
doi: 10.14102/j.cnki.0254-5861.2022-0089
Abstract:
Introducing inorganic cation into hybrid organic-inorganic perovskites (HOIPs) has attracted great attention because of the enhancement stabilities without sacrificing their excellent optoelectronic properties. Here, we introduce Cs and Rb into MAPbI1.8Br1.2 single crystals (SCs) to dig out the mixed cation effect on optoelectronic performances and phase stabilities. Both Rb and Cs can increase the lattice capacity, which is sufficient to relieve the lattice stress caused by photon energy, thus achieving the purpose of stabilizing the lattice structure and inhibiting migration of halide ions, compared with MAPbI1.8Br1.2 SC. On the other hand, the smaller polarity of Rb and Cs reduces the electron-phonon coupling, thus significantly inhibiting the migration of halide ions. Meanwhile, through planar photo-detectors, MA0.9Cs0.1PbI1.8Br1.2-based device behaves much excellent optoelectronic performance (R = 0.170 A/W, EQE = 51.39 %, D* = 4.42 × 1012 Jones, on/off ratio: ~522).
Introducing inorganic cation into hybrid organic-inorganic perovskites (HOIPs) has attracted great attention because of the enhancement stabilities without sacrificing their excellent optoelectronic properties. Here, we introduce Cs and Rb into MAPbI1.8Br1.2 single crystals (SCs) to dig out the mixed cation effect on optoelectronic performances and phase stabilities. Both Rb and Cs can increase the lattice capacity, which is sufficient to relieve the lattice stress caused by photon energy, thus achieving the purpose of stabilizing the lattice structure and inhibiting migration of halide ions, compared with MAPbI1.8Br1.2 SC. On the other hand, the smaller polarity of Rb and Cs reduces the electron-phonon coupling, thus significantly inhibiting the migration of halide ions. Meanwhile, through planar photo-detectors, MA0.9Cs0.1PbI1.8Br1.2-based device behaves much excellent optoelectronic performance (R = 0.170 A/W, EQE = 51.39 %, D* = 4.42 × 1012 Jones, on/off ratio: ~522).
2022, 41(5): 220508
doi: 10.14102/j.cnki.0254-5861.2022-0092
Abstract:
Low-cost and high-energy-density manganese-based compounds are promising cathode materials for rechargeable aqueous zinc-ion batteries (AZIBs), however, they often experience cycling instability issues and inferior rate capability. Herein, we report a new layered manganese-based cathode material, ZnMn3O7 (ZMO), which possesses a large interlayer spacing of 4.8 Å and allows the intercalation of ~1.23 Zn-ions per formula unit (corresponding to a capacity of ~170 mAh/g). Importantly, ZMO exhibits good cycling stability (72.9% capacity retention over 400 cycles), ultrafast-charging capability (73% state of charge in 1.5 min), and an ultrahigh power density (3510 W/kg at 88 Wh/kg). Through kinetic characterization, the favorable diffusion of ions and the dominant capacitor contribution are found to be conducive to the achievement of superior fast charging capability. Furthermore, the charge storage mechanism is revealed by ex-situ XRD and ex-situ XPS. This work may shed light on the design of high-performance electrode materials for AZIBs.
Low-cost and high-energy-density manganese-based compounds are promising cathode materials for rechargeable aqueous zinc-ion batteries (AZIBs), however, they often experience cycling instability issues and inferior rate capability. Herein, we report a new layered manganese-based cathode material, ZnMn3O7 (ZMO), which possesses a large interlayer spacing of 4.8 Å and allows the intercalation of ~1.23 Zn-ions per formula unit (corresponding to a capacity of ~170 mAh/g). Importantly, ZMO exhibits good cycling stability (72.9% capacity retention over 400 cycles), ultrafast-charging capability (73% state of charge in 1.5 min), and an ultrahigh power density (3510 W/kg at 88 Wh/kg). Through kinetic characterization, the favorable diffusion of ions and the dominant capacitor contribution are found to be conducive to the achievement of superior fast charging capability. Furthermore, the charge storage mechanism is revealed by ex-situ XRD and ex-situ XPS. This work may shed light on the design of high-performance electrode materials for AZIBs.
2022, 41(5): 220509
doi: 10.14102/j.cnki.0254-5861.2022-0107
Abstract:
The quasi-homogeneous photocatalytic system can be formed by iodide ions induced fragmented and ultrathin structured TP-PCN. The TP-PCN possesses abundant edge active sites, which can greatly enhance the O2 adsorption/activation capacity and the 2e- ORR selectivity. As expected, the quasi-homogeneous system affords a remarkably increased photocatalytic H2O2 production activity.![]()
