Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change challenges.Many technical pathways have bee...Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change challenges.Many technical pathways have been proposed to address the challenges.Carbon capture and utilization(CCU) represents one of the approaches and thermochemical CO_(2) splitting driven by thermal energy is a subset of the CCU,which converts the captured CO_(2) into CO and makes it possible to achieve closed-loop carbon recirculation.Redox-active catalysts are among the most critical components of the thermochemical splitting cycles and perovskites are regarded as the most promising catalysts.Here we review the latest advancements in thermochemical cycles based on perovskites,covering thermodynamic principles,material modifications,reaction kinetics,oxygen pressure control,circular strategies,and demonstrations to provide a comprehensive overview of the topical area.Thermochemical cycles based on such materials require the consideration of trade-off between cost and efficiency,which is related to actual material used,operation mode,oxygen removal,and heat recovery.Lots of efforts have been made towards improving reaction rates,conversion efficiency and cycling stability,materials related research has been lacking-a key aspect affecting the performance across all above aspects.Double perovskites and composite perovskites arise recently as a potentially promising addition to material candidates.For such materials,more effective oxygen removal would be needed to enhance the overall efficiency,for which thermochemical or electrochemical oxygen pumps could contribute to efficient oxygen removal as well as serve as means for inert gas regeneration.The integration of thermochemical CO_(2) splitting process with downstream fuel production and other processes could reduce costs and increase efficiency of the technology.This represents one of the directions for the future research.展开更多
Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like cov...Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like covalent organic framework(COF)to form a step-scheme(S-scheme)photocata-lyst for H_(2)O_(2)production.The as-prepared S-scheme photocatalyst exhibits a broad light absorption range with an edge at 810 nm owing to the synergistic effect between the ZnSe QDs and COF.The S-scheme charge-carrier transfer mechanism is validated by performing Fermi level calculations and in-situ X-ray photoelectron and femtosecond transient absorption spectroscopies.Photolumi-nescence,time-resolved photoluminescence,photocurrent response,electrochemical impedance spectroscopy,and electron paramagnetic resonance results show that the S-scheme heterojunction not only promotes charge carrier separation but also boosts the redox ability,resulting in enhanced photocatalytic performance.Remarkably,a 10%-ZnSe QD/COF has excellent photocatalytic H_(2)O_(2)-production activity,and the optimal S-scheme composite with ethanol as the hole scavenger yields a H_(2)O_(2)-production rate of 1895 mol g^(-1)h-1.This study presents an example of a high-performance organic/inorganic S-scheme photocatalyst for H_(2)O_(2)production.展开更多
The development of an efficient artificial H_(2)O_(2)photosynthesis system is a challenging work using H_(2)O and O_(2)as starting materials.Herein,3D In2.77S_(4)nanoflower precursor was in-situ deposited on K^(+)-dop...The development of an efficient artificial H_(2)O_(2)photosynthesis system is a challenging work using H_(2)O and O_(2)as starting materials.Herein,3D In2.77S_(4)nanoflower precursor was in-situ deposited on K^(+)-doped g-C_(3)N_(4)(KCN)nanosheets using a solvothermal method,then In2.77S_(4)/KCN(IS/KCN)het-erojunction with an intimate interface was obtained after a calcination process.The investigation shows that the photocatalytic H_(2)O_(2)production rate of 50IS/KCN can reach up to 1.36 mmol g^(-1)h^(-1)without any sacrificial reagents under visible light irradiation,which is 9.2 times and 4.1 times higher than that of KCN and In2.77S_(4),respectively.The enhanced activity of the above composite can be mainly attributed to the S-scheme charge transfer route between KCN and In2.77S_(4)according to density functional theory calculations,electron paramagnetic resonance and free radical capture tests,leading to an expanded light response range and rapid charge separation at their interface,as well as preserving the active electrons and holes for H_(2)O_(2)production.Besides,the unique 3D nanostructure and surface hydrophobicity of IS/KCN facilitate the diffusion and transportation of O_(2)around the active centers,the energy barriers of O_(2)protonation and H_(2)O_(2)desorption steps are ef-fectively reduced over the composite.In addition,this system also exhibits excellent light harvesting ability and stability.This work provides a potential strategy to explore a sustainable H_(2)O_(2)photo-synthesis pathway through the design of heterojunctions with intimate interfaces and desired reac-tion thermodynamics and kinetics.展开更多
The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these pollutants.Fenton system is one of the most widely used technologies to solve this probl...The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these pollutants.Fenton system is one of the most widely used technologies to solve this problem.The original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic contaminants.However,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and storage.The introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in situ.This review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical reaction.The mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed systematically.This review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.展开更多
The continuous and excessive emission of CO_(2)into the atmosphere presents a pressing challenge for global sustainable development.In response,researchers have been devoting significant efforts to develop methods for...The continuous and excessive emission of CO_(2)into the atmosphere presents a pressing challenge for global sustainable development.In response,researchers have been devoting significant efforts to develop methods for converting CO_(2)into valuable chemicals and fuels.These conversions have the potential to establish a closed artificial carbon cycle and provide an alternative resource to depleting fossil fuels.Among the various conversion routes,thermochemical CO_(2)reduction stands out as a promising candidate for industrialization.Within the realm of heterogeneous catalysis,single atom catalysts(SACs)have garnered significant attention.The utilization of SACs offers tremendous potential for enhancing catalytic performance.To achieve optimal activity and selectivity of SACs in CO_(2)thermochemical reduction reactions,a comprehensive understanding of key factors such as single atom metal-support interactions,chemical coordination,and accessibility of active sites is crucial.Despite extensive research in this field,the atomic-scale reaction mechanisms in different chemical environments remain largely unexplored.While SACs have been found successful applications in electrochemical and photochemical CO_(2)reduction reactions,their implementation in thermochemical CO_(2)reduction encounters challenges due to the sintering and/or agglomeration effects that occur at elevated temperatures.In this review,we present a unique approach that combines theoretical understanding with experimental strategies to guide researchers in the design of controlled and thermally stable SACs.By elucidating the underlying principles,we aim to enable the creation of SACs that exhibit stable and efficient catalytic activity for thermochemical CO_(2)reduction reactions.Subsequently,we provide a comprehensive overview of recent literature on noble metal-and transition metal-based SACs for thermochemical CO_(2)reduction.The current review is focused on certain CO_(2)-derived products involving one step reduction only for simplicity and for better understanding the SACs enhancement mechanism.We emphasize various synthesis methods employed and highlight the catalytic activity of these SACs.Finally,we delve into the perspectives and challenges associated with SACs in the context of thermochemical CO_(2)reduction reactions,providing valuable insights for future research endeavor.Through this review,we aim to contribute to the advancement of SACs in the field of thermochemical CO_(2)reduction,shedding light on their potential as effective catalysts and addressing the challenges that need to be overcome for their successful implementation as paradigm shift in catalysis.展开更多
Constructing a step-scheme heterojunction at the interface between two semiconductors is an efficient way to optimize the redox ability and accelerate the charge carrier separation of a photocatalytic system for achie...Constructing a step-scheme heterojunction at the interface between two semiconductors is an efficient way to optimize the redox ability and accelerate the charge carrier separation of a photocatalytic system for achieving high photocatalytic performance.In this study,we prepared a hierarchical ZnO@ZnS step-scheme photocatalyst by incorporating ZnS into the outer shell of hollow ZnO microspheres via a simple in situ sulfidation strategy.The ZnO@ZnS step-scheme photocatalysts had a large surface area,high light utilization capacity,and superior separation efficiency for photogenerated charge carriers.In addition,the material simulation revealed that the formation of the step-scheme heterojunction between ZnO and ZnS was due to the presence of the built-in electric field.Our study paves the way for design of high-performance photocatalysts for H_(2) production.展开更多
Graphitic carbon nitride(g-C_(3)N_(4))has attracted great interest in photocatalysis and photoelectrocatalysis.However,their poor hydrophilicity poses a great challenge for their applications in aqueous environment.He...Graphitic carbon nitride(g-C_(3)N_(4))has attracted great interest in photocatalysis and photoelectrocatalysis.However,their poor hydrophilicity poses a great challenge for their applications in aqueous environment.Here,we demonstrate synthesis of a hydrophilic bi-functional hierarchical architecture by the assembly of B-doped g-C_(3)N_(4)nanoplatelets.Such hierarchical B-doped g-C_(3)N_(4)material enables full utilization of their highly enhanced visible light absorption and photogenerated carrier separation in aqueous medium,leading to an excellent photocatalytic H_(2)O_(2)production rate of 4240.3μM g^(-1)h^(-1),2.84,2.64 and 2.13 times higher than that of the bulk g-C_(3)N_(4),g-C_(3)N_(4)nanoplatelets and bulk B doped g-C_(3)N_(4),respectively.Photoanodes based on these hierarchical architectures can generate an unprecedented photocurrent density of 1.72 m A cm^(-2)at 1.23 V under AM 1.5 G illumination for photoelectrochemical water splitting.This work makes a fundamental improvement towards large-scale exploitation of highly active,hydrophilic and stable metal-free g-C_(3)N_(4)photocatalysts for various practical applications.展开更多
Here,CuO nanorods fabricated via pulsed laser ablation in liquids were decorated with Ir,Pd,and Ru NPs(loading~7 wt%) through pulsed laser irradiation in the liquids process.The resulting NPs-decorated CuO nanorods we...Here,CuO nanorods fabricated via pulsed laser ablation in liquids were decorated with Ir,Pd,and Ru NPs(loading~7 wt%) through pulsed laser irradiation in the liquids process.The resulting NPs-decorated CuO nanorods were characterized spectroscopically and employed as multifunctional electrocatalysts in OER,HER,and the furfural oxidation reactions(FOR).Ir-CuO nanorods afford the lowest overpotential of~345 mV(HER) and 414 mV(OER) at 10 mA cm^(-2),provide the highest 2-furoic acid yield(~10.85 mM) with 64.9% selectivity,and the best Faradaic efficiency~72.7% in 2 h of FOR at 1.58 V(vs.RHE).In situ electrochemical-Raman analysis of the Ir-CuO detects the formation of the crucial intermediates,such as Cu(Ⅲ)-oxide,Cu(OH)_(2),and Ir_x(OH)_y,on the electrode-electrolyte surface,which act as a promoter for HER and OER.The Ir-CuO ‖ Ir-CuO in a coupled HER and FOR-electrolyzer operates at~200 mV lower voltage,compared with the conventional electrolyzer and embodies the dual advantage of energy-saving H_(2) and 2-furoic acid production.展开更多
为保障工作人员在硫化氢(H_(2)S)泄漏工况下的生命安全,以东南部海域某高含硫油田开发工程为例,结合国内第一艘圆筒形浮式生产储油卸油装置(Floating Production Storage and Offloading,FPSO)的结构特点,设计一种适用于高含H_(2)S油气...为保障工作人员在硫化氢(H_(2)S)泄漏工况下的生命安全,以东南部海域某高含硫油田开发工程为例,结合国内第一艘圆筒形浮式生产储油卸油装置(Floating Production Storage and Offloading,FPSO)的结构特点,设计一种适用于高含H_(2)S油气田的FPSO应急空气呼吸系统。研究表明:该空气呼吸系统安全可靠、占地面积小、使用方便。研究成果可为H_(2)S防护设计提供一定参考。展开更多
文摘Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change challenges.Many technical pathways have been proposed to address the challenges.Carbon capture and utilization(CCU) represents one of the approaches and thermochemical CO_(2) splitting driven by thermal energy is a subset of the CCU,which converts the captured CO_(2) into CO and makes it possible to achieve closed-loop carbon recirculation.Redox-active catalysts are among the most critical components of the thermochemical splitting cycles and perovskites are regarded as the most promising catalysts.Here we review the latest advancements in thermochemical cycles based on perovskites,covering thermodynamic principles,material modifications,reaction kinetics,oxygen pressure control,circular strategies,and demonstrations to provide a comprehensive overview of the topical area.Thermochemical cycles based on such materials require the consideration of trade-off between cost and efficiency,which is related to actual material used,operation mode,oxygen removal,and heat recovery.Lots of efforts have been made towards improving reaction rates,conversion efficiency and cycling stability,materials related research has been lacking-a key aspect affecting the performance across all above aspects.Double perovskites and composite perovskites arise recently as a potentially promising addition to material candidates.For such materials,more effective oxygen removal would be needed to enhance the overall efficiency,for which thermochemical or electrochemical oxygen pumps could contribute to efficient oxygen removal as well as serve as means for inert gas regeneration.The integration of thermochemical CO_(2) splitting process with downstream fuel production and other processes could reduce costs and increase efficiency of the technology.This represents one of the directions for the future research.
文摘Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like covalent organic framework(COF)to form a step-scheme(S-scheme)photocata-lyst for H_(2)O_(2)production.The as-prepared S-scheme photocatalyst exhibits a broad light absorption range with an edge at 810 nm owing to the synergistic effect between the ZnSe QDs and COF.The S-scheme charge-carrier transfer mechanism is validated by performing Fermi level calculations and in-situ X-ray photoelectron and femtosecond transient absorption spectroscopies.Photolumi-nescence,time-resolved photoluminescence,photocurrent response,electrochemical impedance spectroscopy,and electron paramagnetic resonance results show that the S-scheme heterojunction not only promotes charge carrier separation but also boosts the redox ability,resulting in enhanced photocatalytic performance.Remarkably,a 10%-ZnSe QD/COF has excellent photocatalytic H_(2)O_(2)-production activity,and the optimal S-scheme composite with ethanol as the hole scavenger yields a H_(2)O_(2)-production rate of 1895 mol g^(-1)h-1.This study presents an example of a high-performance organic/inorganic S-scheme photocatalyst for H_(2)O_(2)production.
文摘The development of an efficient artificial H_(2)O_(2)photosynthesis system is a challenging work using H_(2)O and O_(2)as starting materials.Herein,3D In2.77S_(4)nanoflower precursor was in-situ deposited on K^(+)-doped g-C_(3)N_(4)(KCN)nanosheets using a solvothermal method,then In2.77S_(4)/KCN(IS/KCN)het-erojunction with an intimate interface was obtained after a calcination process.The investigation shows that the photocatalytic H_(2)O_(2)production rate of 50IS/KCN can reach up to 1.36 mmol g^(-1)h^(-1)without any sacrificial reagents under visible light irradiation,which is 9.2 times and 4.1 times higher than that of KCN and In2.77S_(4),respectively.The enhanced activity of the above composite can be mainly attributed to the S-scheme charge transfer route between KCN and In2.77S_(4)according to density functional theory calculations,electron paramagnetic resonance and free radical capture tests,leading to an expanded light response range and rapid charge separation at their interface,as well as preserving the active electrons and holes for H_(2)O_(2)production.Besides,the unique 3D nanostructure and surface hydrophobicity of IS/KCN facilitate the diffusion and transportation of O_(2)around the active centers,the energy barriers of O_(2)protonation and H_(2)O_(2)desorption steps are ef-fectively reduced over the composite.In addition,this system also exhibits excellent light harvesting ability and stability.This work provides a potential strategy to explore a sustainable H_(2)O_(2)photo-synthesis pathway through the design of heterojunctions with intimate interfaces and desired reac-tion thermodynamics and kinetics.
基金supported by the National Natural Science Foundation of China(No.21906056No.22176060)+2 种基金the Undergraduate Training Program on Innovation and Entrepreneurship(S202110251087)the Science and Technology Commission of Shanghai Municipality(22ZR1418600)Shanghai Municipal Science and Technology(No.20DZ2250400).
文摘The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these pollutants.Fenton system is one of the most widely used technologies to solve this problem.The original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic contaminants.However,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and storage.The introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in situ.This review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical reaction.The mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed systematically.This review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.
基金support by Khalifa University through CIRA-2020-077 and RC2-2018-024 grants。
文摘The continuous and excessive emission of CO_(2)into the atmosphere presents a pressing challenge for global sustainable development.In response,researchers have been devoting significant efforts to develop methods for converting CO_(2)into valuable chemicals and fuels.These conversions have the potential to establish a closed artificial carbon cycle and provide an alternative resource to depleting fossil fuels.Among the various conversion routes,thermochemical CO_(2)reduction stands out as a promising candidate for industrialization.Within the realm of heterogeneous catalysis,single atom catalysts(SACs)have garnered significant attention.The utilization of SACs offers tremendous potential for enhancing catalytic performance.To achieve optimal activity and selectivity of SACs in CO_(2)thermochemical reduction reactions,a comprehensive understanding of key factors such as single atom metal-support interactions,chemical coordination,and accessibility of active sites is crucial.Despite extensive research in this field,the atomic-scale reaction mechanisms in different chemical environments remain largely unexplored.While SACs have been found successful applications in electrochemical and photochemical CO_(2)reduction reactions,their implementation in thermochemical CO_(2)reduction encounters challenges due to the sintering and/or agglomeration effects that occur at elevated temperatures.In this review,we present a unique approach that combines theoretical understanding with experimental strategies to guide researchers in the design of controlled and thermally stable SACs.By elucidating the underlying principles,we aim to enable the creation of SACs that exhibit stable and efficient catalytic activity for thermochemical CO_(2)reduction reactions.Subsequently,we provide a comprehensive overview of recent literature on noble metal-and transition metal-based SACs for thermochemical CO_(2)reduction.The current review is focused on certain CO_(2)-derived products involving one step reduction only for simplicity and for better understanding the SACs enhancement mechanism.We emphasize various synthesis methods employed and highlight the catalytic activity of these SACs.Finally,we delve into the perspectives and challenges associated with SACs in the context of thermochemical CO_(2)reduction reactions,providing valuable insights for future research endeavor.Through this review,we aim to contribute to the advancement of SACs in the field of thermochemical CO_(2)reduction,shedding light on their potential as effective catalysts and addressing the challenges that need to be overcome for their successful implementation as paradigm shift in catalysis.
文摘Constructing a step-scheme heterojunction at the interface between two semiconductors is an efficient way to optimize the redox ability and accelerate the charge carrier separation of a photocatalytic system for achieving high photocatalytic performance.In this study,we prepared a hierarchical ZnO@ZnS step-scheme photocatalyst by incorporating ZnS into the outer shell of hollow ZnO microspheres via a simple in situ sulfidation strategy.The ZnO@ZnS step-scheme photocatalysts had a large surface area,high light utilization capacity,and superior separation efficiency for photogenerated charge carriers.In addition,the material simulation revealed that the formation of the step-scheme heterojunction between ZnO and ZnS was due to the presence of the built-in electric field.Our study paves the way for design of high-performance photocatalysts for H_(2) production.
基金financially supported by the National Natural Science Foundation of China(U1663225)the Changjiang Scholar Program of Chinese Ministry of Education(IRT15R52)the program of Introducing Talents of Discipline to Universities-Plan 111(B20002)of Ministry of Science and Technology and the Ministry of Education of China and the project “Depollut Air”of Interreg V France-WallonieVlaanderen。
文摘Graphitic carbon nitride(g-C_(3)N_(4))has attracted great interest in photocatalysis and photoelectrocatalysis.However,their poor hydrophilicity poses a great challenge for their applications in aqueous environment.Here,we demonstrate synthesis of a hydrophilic bi-functional hierarchical architecture by the assembly of B-doped g-C_(3)N_(4)nanoplatelets.Such hierarchical B-doped g-C_(3)N_(4)material enables full utilization of their highly enhanced visible light absorption and photogenerated carrier separation in aqueous medium,leading to an excellent photocatalytic H_(2)O_(2)production rate of 4240.3μM g^(-1)h^(-1),2.84,2.64 and 2.13 times higher than that of the bulk g-C_(3)N_(4),g-C_(3)N_(4)nanoplatelets and bulk B doped g-C_(3)N_(4),respectively.Photoanodes based on these hierarchical architectures can generate an unprecedented photocurrent density of 1.72 m A cm^(-2)at 1.23 V under AM 1.5 G illumination for photoelectrochemical water splitting.This work makes a fundamental improvement towards large-scale exploitation of highly active,hydrophilic and stable metal-free g-C_(3)N_(4)photocatalysts for various practical applications.
基金supported by the Korea Basic Science Institute (National research Facilities and Equipment Center) grant funded by the Ministry of Education. (2019R1A6C1010042, 2021R1A6C103A427)the financial support from the National Research Foundation of Korea (NRF), (2022R1A2C2010686, 2022R1A4A3033528, 2021R1I1A1A01060380, 2019H1D3A1A01071209)。
文摘Here,CuO nanorods fabricated via pulsed laser ablation in liquids were decorated with Ir,Pd,and Ru NPs(loading~7 wt%) through pulsed laser irradiation in the liquids process.The resulting NPs-decorated CuO nanorods were characterized spectroscopically and employed as multifunctional electrocatalysts in OER,HER,and the furfural oxidation reactions(FOR).Ir-CuO nanorods afford the lowest overpotential of~345 mV(HER) and 414 mV(OER) at 10 mA cm^(-2),provide the highest 2-furoic acid yield(~10.85 mM) with 64.9% selectivity,and the best Faradaic efficiency~72.7% in 2 h of FOR at 1.58 V(vs.RHE).In situ electrochemical-Raman analysis of the Ir-CuO detects the formation of the crucial intermediates,such as Cu(Ⅲ)-oxide,Cu(OH)_(2),and Ir_x(OH)_y,on the electrode-electrolyte surface,which act as a promoter for HER and OER.The Ir-CuO ‖ Ir-CuO in a coupled HER and FOR-electrolyzer operates at~200 mV lower voltage,compared with the conventional electrolyzer and embodies the dual advantage of energy-saving H_(2) and 2-furoic acid production.
文摘为保障工作人员在硫化氢(H_(2)S)泄漏工况下的生命安全,以东南部海域某高含硫油田开发工程为例,结合国内第一艘圆筒形浮式生产储油卸油装置(Floating Production Storage and Offloading,FPSO)的结构特点,设计一种适用于高含H_(2)S油气田的FPSO应急空气呼吸系统。研究表明:该空气呼吸系统安全可靠、占地面积小、使用方便。研究成果可为H_(2)S防护设计提供一定参考。
