Electrochemical water splitting has attracted considerable attention for the production of hydrogen fuel by using renewable energy resources.However,the sluggish reaction kinetics make it essential to explore precious...Electrochemical water splitting has attracted considerable attention for the production of hydrogen fuel by using renewable energy resources.However,the sluggish reaction kinetics make it essential to explore precious-metal-free electrocatalysts with superior activity and long-term stability.Tremendous efforts have been made in exploring electrocatalysts to reduce the energy barriers and improve catalytic efficiency.This review summarizes different categories of precious-metal-free electrocatalysts developed in the past 5 years for alkaline water splitting.The design strategies for optimizing the electronic and geometric structures of electrocatalysts with enhanced catalytic performance are discussed,including composition modulation,defect engineering,and structural engineering.Particularly,the advancement of operando/in situ characterization techniques toward the understanding of structural evolution,reaction intermediates,and active sites during the water splitting process are summarized.Finally,current challenges and future perspectives toward achieving efficient catalyst systems for industrial applications are proposed.This review will provide insights and strategies to the design of precious-metalfree electrocatalysts and inspire future research in alkaline water splitting.展开更多
The introduction of plasmons is an important method to solve the insufficient utilization of the full spectrum of solar energy by semiconductor catalysts.However,semiconductor catalysts combined with traditional noble...The introduction of plasmons is an important method to solve the insufficient utilization of the full spectrum of solar energy by semiconductor catalysts.However,semiconductor catalysts combined with traditional noble metal plasmons(Au,Ag)can only extend the absorption spectrum to partially visible light.In order to further improve the photoenergy absorption efficiency of catalysts,they need to be able to effectively utilize near-infrared light,which has become a new research direction.Recent studies have shown that traditional noble metal plasmons can absorb a part of NIR through special morphology,size control and material composite.At the same time,gratifying achievements have been made in the application of plasmonic semiconductors with broad spectrum absorption in catalysis.This article reviews the principles of generating and regulating plasmonic effects in different catalytic systems.The applications of plasmon absorption of near-infrared light in energy conversion and environmental remediation have also been presented.展开更多
The quest for net-zero emissions highlights the signifi-cance of hydrogen as a clean energy carrier,necessitating efficient production methods.Electrochemical water splitting emerges as a crucial method for hydrogen g...The quest for net-zero emissions highlights the signifi-cance of hydrogen as a clean energy carrier,necessitating efficient production methods.Electrochemical water splitting emerges as a crucial method for hydrogen generation,with its further advancement hinging on the development of effective bifunctional catalysts that are efficient in both oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).In this study,we develop the bifunctional electrocatalyst NiFe(OH)x/Fe/graphene through a simple solution-corrosion approach.The overpotentials required for OER and HER to achieve a current density of 10 mA cm^(−2) are 237 and 42 mV,respectively,while the overall water splitting occurs at a low cell voltage of 1.51 V for the same current density.Remarkably,the catalyst displays robust stability exceeding 70 h at 20 mA cm^(−2) in 1 M KOH.When scaled to 10×10 cm^(2),its performance is comparable to that of a smaller size 0.5×0.5 cm^(2) electrode,indicating the scalability of our method and potential for industrial-scale hydrogen production.Trace incorporation of iron and the facilitation by graphene modify the electronic structures and coordination environment in the amorphous NiFe(OH)x/Fe/graphene composite.This alteration enhances the distribution of active sites and reduces kinetic barriers for both HER and OER,thereby increasing its bifunctional catalytic activity.This study not only introduces a novel catalyst design that incorporates in-situ Fe metal powder within OER-active catalysts to generate HER active sites for enabling bifunctionality,but also offers a pathway to manufacture high performance electrocatalysts for industrial applications.展开更多
基金This study was funded by the Australian Research Council(FT170100224)the Australian Renewable Energy Agency+1 种基金National Natural Science Foundation of China(21825501)the Tsinghua University Initiative Scientific Research Program.
文摘Electrochemical water splitting has attracted considerable attention for the production of hydrogen fuel by using renewable energy resources.However,the sluggish reaction kinetics make it essential to explore precious-metal-free electrocatalysts with superior activity and long-term stability.Tremendous efforts have been made in exploring electrocatalysts to reduce the energy barriers and improve catalytic efficiency.This review summarizes different categories of precious-metal-free electrocatalysts developed in the past 5 years for alkaline water splitting.The design strategies for optimizing the electronic and geometric structures of electrocatalysts with enhanced catalytic performance are discussed,including composition modulation,defect engineering,and structural engineering.Particularly,the advancement of operando/in situ characterization techniques toward the understanding of structural evolution,reaction intermediates,and active sites during the water splitting process are summarized.Finally,current challenges and future perspectives toward achieving efficient catalyst systems for industrial applications are proposed.This review will provide insights and strategies to the design of precious-metalfree electrocatalysts and inspire future research in alkaline water splitting.
基金Supported by the State Key Laboratory of Electrical Insulation and Power Equipment at Xi'an Jiaotong University,China(No.IPE19203).
文摘The introduction of plasmons is an important method to solve the insufficient utilization of the full spectrum of solar energy by semiconductor catalysts.However,semiconductor catalysts combined with traditional noble metal plasmons(Au,Ag)can only extend the absorption spectrum to partially visible light.In order to further improve the photoenergy absorption efficiency of catalysts,they need to be able to effectively utilize near-infrared light,which has become a new research direction.Recent studies have shown that traditional noble metal plasmons can absorb a part of NIR through special morphology,size control and material composite.At the same time,gratifying achievements have been made in the application of plasmonic semiconductors with broad spectrum absorption in catalysis.This article reviews the principles of generating and regulating plasmonic effects in different catalytic systems.The applications of plasmon absorption of near-infrared light in energy conversion and environmental remediation have also been presented.
基金the funding support from the Australian Research Council(ARC)and the Australian Renewable Energy Agencythe funding support from the Macquarie University Research Fellowships.
文摘The quest for net-zero emissions highlights the signifi-cance of hydrogen as a clean energy carrier,necessitating efficient production methods.Electrochemical water splitting emerges as a crucial method for hydrogen generation,with its further advancement hinging on the development of effective bifunctional catalysts that are efficient in both oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).In this study,we develop the bifunctional electrocatalyst NiFe(OH)x/Fe/graphene through a simple solution-corrosion approach.The overpotentials required for OER and HER to achieve a current density of 10 mA cm^(−2) are 237 and 42 mV,respectively,while the overall water splitting occurs at a low cell voltage of 1.51 V for the same current density.Remarkably,the catalyst displays robust stability exceeding 70 h at 20 mA cm^(−2) in 1 M KOH.When scaled to 10×10 cm^(2),its performance is comparable to that of a smaller size 0.5×0.5 cm^(2) electrode,indicating the scalability of our method and potential for industrial-scale hydrogen production.Trace incorporation of iron and the facilitation by graphene modify the electronic structures and coordination environment in the amorphous NiFe(OH)x/Fe/graphene composite.This alteration enhances the distribution of active sites and reduces kinetic barriers for both HER and OER,thereby increasing its bifunctional catalytic activity.This study not only introduces a novel catalyst design that incorporates in-situ Fe metal powder within OER-active catalysts to generate HER active sites for enabling bifunctionality,but also offers a pathway to manufacture high performance electrocatalysts for industrial applications.
