Catalysis research has witnessed remarkable progress with the advent of in situ and operando techniques.These methods enable the study of catalysts under actual operating conditions,providing unprecedented insights in...Catalysis research has witnessed remarkable progress with the advent of in situ and operando techniques.These methods enable the study of catalysts under actual operating conditions,providing unprecedented insights into catalytic mechanisms and dynamic catalyst behavior.This review discusses key in situ techniques and their applications in catalysis research.Advances in in situ electron microscopy allow direct visualization of catalysts at the atomic scale under reaction conditions.In situ spectroscopy techniques like X-ray absorption spectroscopy and nuclear magnetic resonance spectroscopy can track chemical states and reveal transient intermediates.Synchrotron-based techniques offer enhanced capabilities for in situ studies.The integration of in situ methods with machine learning and computational modeling provides a powerful approach to accelerate catalyst optimization.However,challenges remain regarding radiation damage,instrumentation limitations,and data interpretation.Overall,continued development of multi-modal in situ techniques is pivotal for addressing emerging challenges and opportunities in catalysis research and technology.展开更多
The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation...The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.展开更多
There is an urgent need to develop innovative electrochemical energy storage devices that can offer high energy density,long lifespan,excellent rate capability,and improved security.For the electrochemical system,the ...There is an urgent need to develop innovative electrochemical energy storage devices that can offer high energy density,long lifespan,excellent rate capability,and improved security.For the electrochemical system,the electrode interphase,namely the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)play crucial roles in the operating mechanism,kinetics,and overall performance of the battery.However,the in-depth investigation of the unstable and complex electrode interphase is limited by the unavoidable air and moisture contact during the material transfer process and probable high-energy radiation damage in the characterization procedure.Recently,cryogenic techniques and in situ techniques have been developed and applied in the electrode interphase research to settle the radiation damage and air erosion,respectively.However,there has not been a special review that summarizes the relevant methods,so a systematic review is very important to accelerate the development.In this review,we summarize these two state-of-the-art methods,including their working principle,characterization process,advantages,and applications in electrode interphase analysis.And the integrative techniques,which are considered as the future development perspectives,are also discussed.This review can provide important directions for next-generation characterization techniques and strategies to effectively analyze the electrode interphase for advanced batteries.展开更多
Direct seawater electrolysis for hydrogen production has been regarded as a viable route to utilize surplus renewable energy and address the climate crisis.However,the harsh electrochemical environment of seawater,par...Direct seawater electrolysis for hydrogen production has been regarded as a viable route to utilize surplus renewable energy and address the climate crisis.However,the harsh electrochemical environment of seawater,particularly the presence of aggressive Cl^(-),has been proven to be prone to parasitic chloride ion oxidation and corrosion reactions,thus restricting seawater electrolyzer lifetime.Herein,hierarchical structure(Ni,Fe)O(OH)@NiCoS nanorod arrays(NAs)catalysts with heterointerfaces and localized oxygen vacancies were synthesized at nickel foam substrates via the combination of hydrothermal and annealing methods to boost seawater dissociation.The hiera rchical nanostructure of NiCoS NAs enhanced electrode charge transfer rate and active surface area to accelerate oxygen evolution reaction(OER)and generated sulfate gradient layers to repulsive aggressive Cl^(-).The fabricated heterostructure and vacancies of(Ni,Fe)O(OH)tuned catalyst electronic structure into an electrophilic state to enhance the binding affinity of hydroxyl intermediates and facilitate the structural transformation into amorphousγ-NiFeOOH for promoting OER.Furthermore,through operando electrochemistry techniques,we found that theγ-NiFeOOH possessing an unsaturated coordination environment and lattice-oxygen-participated OER mechanism can minimize electrode Cl^(-)corrosion enabled by stabilizing the adsorption of OH*intermediates,making it one of the best OER catalysts in the seawater medium reported to date.Consequently,these catalysts can deliver current densities of 100 and 500 mA cm-2for boosting OER at minimal overpotentials of 245and 316 mV,respectively,and thus prevent chloride ion oxidation simultaneously.Impressively,a highly stable anion exchange membrane(AEM)seawater electrolyzer based on the non-noble metal heterostructure electrodes reached a record low degradation rate under 100μV h-1at constant industrial current densities of 400 and 600 mA cm-2over 300 h,which exhibits a promising future for the nonprecious and stable AEMWE in the direct seawater electrolysis industry.展开更多
Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an ...Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an in-depth understanding of the electrocatalytic behavior of HMFOR has rarely been investigated.Herein,the electrocatalytic mechanism of HMFOR on nickel nitride(Ni3 N)is elucidated by operando X-ray absorption spectroscopy(XAS),in situ Raman,quasi in situ X-ray photoelectron spectroscopy(XPS),and operando electrochemical impedance spectroscopy(EIS),respectively.The activity origin is proved to be Ni^(2+δ)N(OH)ads generated by the adsorbed hydroxyl group.Moreover,HMFOR on Ni3 N relates to a two-step reaction:Initially,the applied potential drives Ni atoms to lose electrons and adsorb OH-after 1.35 VRHE,giving rise to Ni^(2+δ)N(OH)ads with the electrophilic oxygen;then Ni^(2+δ)N(OH)ads seizes protons and electrons from HMF and leaves as H_(2) O spontaneously.Furthermore,the high electrolyte alkalinity favors the HMFOR process due to the increased active species(Ni^(2+δ)N(OH)ads)and the enhanced adsorption of HMF on the Ni3 N surface.This work could provide an in-depth understanding of the electrocatalytic mechanism of HMFOR on Ni3 N and demonstrate the alkalinity effect of the electrolyte on the electrocatalytic performance of HMFOR.展开更多
Copper(Cu)has been regarded as a highly efficient electrocatalyst for the conversion of CO_(2) into a multicarbon product.However,the catalytic mechanism and the active sites of Cu catalysts under operating conditions...Copper(Cu)has been regarded as a highly efficient electrocatalyst for the conversion of CO_(2) into a multicarbon product.However,the catalytic mechanism and the active sites of Cu catalysts under operating conditions still remain elusive.Yang's team applied systematic operando characterization techniques to provide a quantitative analysis of the valence states and the chemical environment of Cu nanocatalysts under electrochemical reaction conditions,which clearly reveal the evolution of Cu nanocatalysts before and after the entire electrochemical CO_(2) reduction.展开更多
Alkalicarbonate-based sorbents(ACSs),including Na_(2)CO_(3)-and K2CO_(3)-based sorbents,are promising for CO_(2)capture.However,the complex sorbent components and operation conditions lead to the versatile kinetics of...Alkalicarbonate-based sorbents(ACSs),including Na_(2)CO_(3)-and K2CO_(3)-based sorbents,are promising for CO_(2)capture.However,the complex sorbent components and operation conditions lead to the versatile kinetics of CO_(2)sorption on these sorbents.This paper proposed that operando modeling and measurements are powerful tools to understand the mechanism of sorbents in real operating conditions,facilitating the sorbent development,reactor design,and operation parameter optimization.It reviewed the theoretical simulation achievements during the development of ACSs.It elucidated the findings obtained by utilizing density functional theory(DFT)calculations,ab initio molecular dynamics(AIMD)simulations,and classical molecular dynamics(CMD)simulations as well.The hygroscopicity of sorbent and the humidity of gas flow are crucial to shifting the carbonation reaction from the gas-solid mode to the gas-liquid mode,boosting the kinetics.Moreover,it briefly introduced a machine learning(ML)approach as a promising method to aid sorbent design.Furthermore,it demonstrated a conceptual compact operando measurement system in order to understand the behavior of ACSs in the real operation process.The proposed measurement system includes a micro fluidizedbed(MFB)reactor for kinetic analysis,a multi-camera sub-system for 3D particle movement tracking,and a combined Raman and IR sub-system for solid/gas components and temperature monitoring.It is believed that this system is useful to evaluate the real-time sorbent performance,validating the theoretical prediction and promoting the industrial scale-up of ACSs for CO_(2)capture.展开更多
Electrocatalytic CO_(2) reduction(ECR)is a promising approach for achieving carbon neutrality due to its ability to convert CO_(2) to valuable chemicals.Recent advances have significantly enhanced the ECR performance ...Electrocatalytic CO_(2) reduction(ECR)is a promising approach for achieving carbon neutrality due to its ability to convert CO_(2) to valuable chemicals.Recent advances have significantly enhanced the ECR performance of various catalysts by tuning their oxidation states,particularly for Cu-based catalysts that can reduce CO_(2) to multiple products.However,the oxidation state of copper(OSCu),especially Cu+,changes during the reaction process,posing significant challenges for both catalyst characterization and performance.In this review,the current understanding of the effect of oxidation states on product selectivity was first discussed.A comprehensive overview of in situ/operando characterization techniques,used to monitor the dynamic evolution of oxidation states during ECR,was then provided.Various strategies for stabilizing oxidation states through modification of catalysts and manipulation of external conditions were discussed.This review aimed to deepen the understanding of oxidation states in ECR and enlighten the development of more efficient electrocatalysts.展开更多
The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited co...The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited cognition of the reaction mechanism greatly hinder its practical application.Here,we demonstrate a dynamic reconstruction behavior induced by sulfur of the iron-nitrogen(Fe-Nx)species in neutral solution.Our developed FeS_(1)N_(3)-OH configuration effectively optimizes the reaction kinetics by regulating the adsorption energy of oxygen intermediates for central catalytic sites.Consequently,this structure exhibits over 363%enhancement in ORR mass activity compared to the pristine FeN_(4) sites under neutral electrolyte.Moreover,a neutral zinc-air battery assembled with this electrocatalyst reached an ultrahigh peak power density(81.2 mW cm^(−2)),robust stability(more than 100 h)as well as superior tolerance to extreme environments(operating between−20°C and 60°C),representing a critical breakthrough for neutral ORR exploration and application.展开更多
基金financially supported by the Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231.
文摘Catalysis research has witnessed remarkable progress with the advent of in situ and operando techniques.These methods enable the study of catalysts under actual operating conditions,providing unprecedented insights into catalytic mechanisms and dynamic catalyst behavior.This review discusses key in situ techniques and their applications in catalysis research.Advances in in situ electron microscopy allow direct visualization of catalysts at the atomic scale under reaction conditions.In situ spectroscopy techniques like X-ray absorption spectroscopy and nuclear magnetic resonance spectroscopy can track chemical states and reveal transient intermediates.Synchrotron-based techniques offer enhanced capabilities for in situ studies.The integration of in situ methods with machine learning and computational modeling provides a powerful approach to accelerate catalyst optimization.However,challenges remain regarding radiation damage,instrumentation limitations,and data interpretation.Overall,continued development of multi-modal in situ techniques is pivotal for addressing emerging challenges and opportunities in catalysis research and technology.
基金the Canadian NRCan OERD Energy Innovation Programthe Natural Sciences and Engineering Research Council of Canada,and the Carbon Solution Program for their financial support.
文摘The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.
基金supported by the National Nature Science Foundation of China(No.22272205,No.22279164)Hunan Provincial Nature Science Foundation of China(No.2022JJ30685)+4 种基金Hunan Provincial Science and Technology Plan Project of China(No.2017TP1001)the Science and Technology Innovation Program of Hunan Province(2023RC3058)the Scientific and Technological Research Program of Chongqing Municipal Education Commission(No.KJZD-M202101401)Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Provincesupport from Science and Technology Innovation Team for Photovoltaic Power and Energy Storage Battery Key Technologies at General University in Hunan Province.D.S.acknowledges support from Young Elite Scientists Sponsorship Program by CAST(No.YESS20220432).
文摘There is an urgent need to develop innovative electrochemical energy storage devices that can offer high energy density,long lifespan,excellent rate capability,and improved security.For the electrochemical system,the electrode interphase,namely the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)play crucial roles in the operating mechanism,kinetics,and overall performance of the battery.However,the in-depth investigation of the unstable and complex electrode interphase is limited by the unavoidable air and moisture contact during the material transfer process and probable high-energy radiation damage in the characterization procedure.Recently,cryogenic techniques and in situ techniques have been developed and applied in the electrode interphase research to settle the radiation damage and air erosion,respectively.However,there has not been a special review that summarizes the relevant methods,so a systematic review is very important to accelerate the development.In this review,we summarize these two state-of-the-art methods,including their working principle,characterization process,advantages,and applications in electrode interphase analysis.And the integrative techniques,which are considered as the future development perspectives,are also discussed.This review can provide important directions for next-generation characterization techniques and strategies to effectively analyze the electrode interphase for advanced batteries.
基金supported by the National Key Research and Development Program of China(2022YFB4002100)the Key Program of the National Natural Science Foundation of China(22090032,22090030)。
文摘Direct seawater electrolysis for hydrogen production has been regarded as a viable route to utilize surplus renewable energy and address the climate crisis.However,the harsh electrochemical environment of seawater,particularly the presence of aggressive Cl^(-),has been proven to be prone to parasitic chloride ion oxidation and corrosion reactions,thus restricting seawater electrolyzer lifetime.Herein,hierarchical structure(Ni,Fe)O(OH)@NiCoS nanorod arrays(NAs)catalysts with heterointerfaces and localized oxygen vacancies were synthesized at nickel foam substrates via the combination of hydrothermal and annealing methods to boost seawater dissociation.The hiera rchical nanostructure of NiCoS NAs enhanced electrode charge transfer rate and active surface area to accelerate oxygen evolution reaction(OER)and generated sulfate gradient layers to repulsive aggressive Cl^(-).The fabricated heterostructure and vacancies of(Ni,Fe)O(OH)tuned catalyst electronic structure into an electrophilic state to enhance the binding affinity of hydroxyl intermediates and facilitate the structural transformation into amorphousγ-NiFeOOH for promoting OER.Furthermore,through operando electrochemistry techniques,we found that theγ-NiFeOOH possessing an unsaturated coordination environment and lattice-oxygen-participated OER mechanism can minimize electrode Cl^(-)corrosion enabled by stabilizing the adsorption of OH*intermediates,making it one of the best OER catalysts in the seawater medium reported to date.Consequently,these catalysts can deliver current densities of 100 and 500 mA cm-2for boosting OER at minimal overpotentials of 245and 316 mV,respectively,and thus prevent chloride ion oxidation simultaneously.Impressively,a highly stable anion exchange membrane(AEM)seawater electrolyzer based on the non-noble metal heterostructure electrodes reached a record low degradation rate under 100μV h-1at constant industrial current densities of 400 and 600 mA cm-2over 300 h,which exhibits a promising future for the nonprecious and stable AEMWE in the direct seawater electrolysis industry.
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(Grant No.:21902047)+1 种基金the Provincial Natural Science Foundation of Hunan(2020JJ5045)the Fundamental Research Funds for the Central Universities(Grant No.531118010127)。
文摘Electro-oxidation of 5-hydroxymethylfurfural(HMFOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of HMF,an in-depth understanding of the electrocatalytic behavior of HMFOR has rarely been investigated.Herein,the electrocatalytic mechanism of HMFOR on nickel nitride(Ni3 N)is elucidated by operando X-ray absorption spectroscopy(XAS),in situ Raman,quasi in situ X-ray photoelectron spectroscopy(XPS),and operando electrochemical impedance spectroscopy(EIS),respectively.The activity origin is proved to be Ni^(2+δ)N(OH)ads generated by the adsorbed hydroxyl group.Moreover,HMFOR on Ni3 N relates to a two-step reaction:Initially,the applied potential drives Ni atoms to lose electrons and adsorb OH-after 1.35 VRHE,giving rise to Ni^(2+δ)N(OH)ads with the electrophilic oxygen;then Ni^(2+δ)N(OH)ads seizes protons and electrons from HMF and leaves as H_(2) O spontaneously.Furthermore,the high electrolyte alkalinity favors the HMFOR process due to the increased active species(Ni^(2+δ)N(OH)ads)and the enhanced adsorption of HMF on the Ni3 N surface.This work could provide an in-depth understanding of the electrocatalytic mechanism of HMFOR on Ni3 N and demonstrate the alkalinity effect of the electrolyte on the electrocatalytic performance of HMFOR.
基金supported by the National Natural Science Foundation of China(No.22071172).
文摘Copper(Cu)has been regarded as a highly efficient electrocatalyst for the conversion of CO_(2) into a multicarbon product.However,the catalytic mechanism and the active sites of Cu catalysts under operating conditions still remain elusive.Yang's team applied systematic operando characterization techniques to provide a quantitative analysis of the valence states and the chemical environment of Cu nanocatalysts under electrochemical reaction conditions,which clearly reveal the evolution of Cu nanocatalysts before and after the entire electrochemical CO_(2) reduction.
基金the Shanghai Sailing Program(Grant No.22YF1429600)the Scientific and Technological Innovation Project of Carbon Emission Peak and Carbon Neutrality of Jiangsu Province(Grant No.BK20220001).
文摘Alkalicarbonate-based sorbents(ACSs),including Na_(2)CO_(3)-and K2CO_(3)-based sorbents,are promising for CO_(2)capture.However,the complex sorbent components and operation conditions lead to the versatile kinetics of CO_(2)sorption on these sorbents.This paper proposed that operando modeling and measurements are powerful tools to understand the mechanism of sorbents in real operating conditions,facilitating the sorbent development,reactor design,and operation parameter optimization.It reviewed the theoretical simulation achievements during the development of ACSs.It elucidated the findings obtained by utilizing density functional theory(DFT)calculations,ab initio molecular dynamics(AIMD)simulations,and classical molecular dynamics(CMD)simulations as well.The hygroscopicity of sorbent and the humidity of gas flow are crucial to shifting the carbonation reaction from the gas-solid mode to the gas-liquid mode,boosting the kinetics.Moreover,it briefly introduced a machine learning(ML)approach as a promising method to aid sorbent design.Furthermore,it demonstrated a conceptual compact operando measurement system in order to understand the behavior of ACSs in the real operation process.The proposed measurement system includes a micro fluidizedbed(MFB)reactor for kinetic analysis,a multi-camera sub-system for 3D particle movement tracking,and a combined Raman and IR sub-system for solid/gas components and temperature monitoring.It is believed that this system is useful to evaluate the real-time sorbent performance,validating the theoretical prediction and promoting the industrial scale-up of ACSs for CO_(2)capture.
基金supported by the National Natural Science Foundation of China(No.52221004)the Shenzhen Science and Technology Program(No.RCJC20221008092758099)+1 种基金the Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation(No.SZPR2023004)the Guangdong Higher Education Institutions Innovative Research Team of Urban Water Cycle and Ecological Safety(No.2023KCXTD053).
文摘Electrocatalytic CO_(2) reduction(ECR)is a promising approach for achieving carbon neutrality due to its ability to convert CO_(2) to valuable chemicals.Recent advances have significantly enhanced the ECR performance of various catalysts by tuning their oxidation states,particularly for Cu-based catalysts that can reduce CO_(2) to multiple products.However,the oxidation state of copper(OSCu),especially Cu+,changes during the reaction process,posing significant challenges for both catalyst characterization and performance.In this review,the current understanding of the effect of oxidation states on product selectivity was first discussed.A comprehensive overview of in situ/operando characterization techniques,used to monitor the dynamic evolution of oxidation states during ECR,was then provided.Various strategies for stabilizing oxidation states through modification of catalysts and manipulation of external conditions were discussed.This review aimed to deepen the understanding of oxidation states in ECR and enlighten the development of more efficient electrocatalysts.
基金financially supported by the National Natural Science Foundation of China(No.21925110,91745113,22102170,21890751)the National Program for Support of Top-Notch Young Professionals+3 种基金the Fundamental Research Funds for the Central Universities(No.WK 2060190084)the Youth Innovation Promotion Association of Chinese academy of Sciences(No.Y201877)the Institute of Energy,Hefei Comprehensive National Science Center(Grant No.21KZS213)the support from the Major/Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology。
文摘The neutral oxygen reduction reaction(ORR)has attracted tremendous attention for its broad prospects in next-generation power storage systems.However,the extremely sluggish cathodic reaction process and the limited cognition of the reaction mechanism greatly hinder its practical application.Here,we demonstrate a dynamic reconstruction behavior induced by sulfur of the iron-nitrogen(Fe-Nx)species in neutral solution.Our developed FeS_(1)N_(3)-OH configuration effectively optimizes the reaction kinetics by regulating the adsorption energy of oxygen intermediates for central catalytic sites.Consequently,this structure exhibits over 363%enhancement in ORR mass activity compared to the pristine FeN_(4) sites under neutral electrolyte.Moreover,a neutral zinc-air battery assembled with this electrocatalyst reached an ultrahigh peak power density(81.2 mW cm^(−2)),robust stability(more than 100 h)as well as superior tolerance to extreme environments(operating between−20°C and 60°C),representing a critical breakthrough for neutral ORR exploration and application.
