Lithium metal batteries(LMBs)represent a promising solution for next-generation energy storage due to their high energy density,but the growth of lithium dendrites presents significant challenges to their performance ...Lithium metal batteries(LMBs)represent a promising solution for next-generation energy storage due to their high energy density,but the growth of lithium dendrites presents significant challenges to their performance and safety.This review provides a comprehensive overview of the mechanisms behind lithium dendrite formation and the role of in situ/operando observation and phase field simulation in understanding and mitigating this issue,The key driving factors of dendrite growth,such as lithium-ion flux heterogeneity,surface defects,and localized stress,are explored through advanced experimental techniques,which enable real-time visualization of dendrite nucleation and growth dynamics.Complementarily,phase field simulations provide insights into subsurface and temporal evolution of dendrites by modeling thermodynamic and kinetic processes,while machine learning techniques optimize simulation accuracy through data-driven parameter refinement.The integration of experimental observations with simulation models holds great potential in improving understanding and predictive capabilities.Despite ongoing progress,challenges remain in resolving technical limitations in observation techniques,improving computational efficiency,and fostering interdisciplinary collaboration.This review highlights the synergy between experimental and computational strategies in advancing the development of LMBs and calls for continued research to overcome existing hurdles and unlock the full potential of lithium metal anodes.展开更多
Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements hav...Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm.展开更多
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge...Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.展开更多
The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusi...The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue.Herein,we employed in situ/operando X-ray absorption spectroscopy(XAS)to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces,respectively,in a real-time condition.After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix(BSOC),we found the Li/S cell showed greatly improved sulfur utilization and longer life span.The operando S Kedge XAS results revealed that the BSOC modification was bi-functional:trapping polysulfides and catalyzing conversion of sulfur species simultaneously.We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection.Our results could offer potential stratagem for designing more advanced Li/S cells.展开更多
The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and go...The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and good charge efficiency.However,due to safety concerns,the depletion of lithium reserves,and the corresponding increase of cost,an alternative battery system becomes more and more desirable.To develop alternative battery systems with low cost and high material abundance,for example,sodium,magnesium,zinc,and calcium,it is important to understand the chemical and electronic structure of materials.Soft X-ray spectroscopy,for example,X-ray absorption spectroscopy(XAS),X-ray emission spectroscopy(XES),and resonant inelastic soft X-ray scattering(RIXS),is an element-specific technique with sensitivity to the local chemical environment and structural order of the element of interest.Modern soft X-ray systems enable operando experiments that can be applied to amorphous and crystalline samples,making it a powerful tool for studying the electronic and structural changes in electrode and electrolyte species.In this article,the application of in situ/operando(soft)X-ray spectroscopy in beyond lithium-ion batteries is reviewed to demonstrate how such spectroscopic characterizations could facilitate the interpretation of interfacial phenomena under in situ/operando condition and subsequent development of the beyond lithium-ion batteries.展开更多
Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applica...Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applications and novel devices constructed in recent years are necessary to be reviewed for inspiring subsequent studies.Hence,we summarize the progress of in-situ/operando techniques employed in rechargeable batteries.The members of this large family are divided into three sections for introduction,including bulk material,electrolyte/electrode interface and gas evolution.In each part,various energy-storage systems are mentioned and the related experimental details as well as data analysis are discussed.The simultaneous strategies of various in-situ methods are highlighted as well.Finally,current challenges and potential solutions are concluded towards the rising influence and enlarged appliance of in-situ/operando techniques in the battery research.展开更多
The increasing demands of multifunctional organic electronics require advanced organic semiconducting materials to be developed and significant improvements to be made to device performance. Thus, it is necessary to g...The increasing demands of multifunctional organic electronics require advanced organic semiconducting materials to be developed and significant improvements to be made to device performance. Thus, it is necessary to gain an in-depth understanding of the film growth process, electronic states, and dynamic structure-property relationship under realistic operation conditions, which can be obtained by in-situ/operando characterization techniques for organic devices. Here, the up-todate developments in the in-situ/operando optical, scanning probe microscopy, and spectroscopy techniques that are employed for studies of film morphological evolution, crystal structures, semiconductor-electrolyte interface properties, and charge carrier dynamics are described and summarized. These advanced technologies leverage the traditional static characterizations into an in-situ and interactive manipulation of organic semiconducting films and devices without sacrificing the resolution, which facilitates the exploration of the intrinsic structure-property relationship of organic materials and the optimization of organic devices for advanced applications.展开更多
Catalysts can significantly promote the reaction dynamics and are therefore considered crucial components for achieving high electrochemical energy conversion efficiency.However,the active sites of the catalysts,parti...Catalysts can significantly promote the reaction dynamics and are therefore considered crucial components for achieving high electrochemical energy conversion efficiency.However,the active sites of the catalysts,particularly for nano-level and atomic-level catalysts commonly undergo reconstruction under practical applications.Therefore,obtaining an in-depth and systematic understanding on the real active sites through in situ/operando characterization techniques is a prerequisite for establishing the structureperformance relationship and guiding the future design of more efficient electrocatalysts.Herein,we summarize the recent progress of in situ/operando characterization techniques for identifying the nature of active sites of electrocatalysts when used in electrocatalytic energy conversion reaction.Specifically,our focus lies in the fundamental principles of various in situ/operando characterization techniques,with particular emphasis on their applications for electrocatalytic reactions.Beyond that,the challenges and perspective insights are also added in the final section to highlight the future direction of this important field.展开更多
Lithium metal anodes,with high theoretical capacity and low reduction potential,are widely regarded as the ideal solution to overcome the energy-density limits of current batteries.However,uncontrolled Li dendrite gro...Lithium metal anodes,with high theoretical capacity and low reduction potential,are widely regarded as the ideal solution to overcome the energy-density limits of current batteries.However,uncontrolled Li dendrite growth,repeated rupture and reconstruction of solid electrolyte interphase(SEI),and irreversible side reactions severely impede their commercial viability.A deep understanding of these complex failure mechanisms and their intrinsic links to electrochemical performance is essential to surmount these challenges.Conventional ex situ techniques only provide static snapshots and may distort transient information.In contrast,in situ/operando characterization enables real-time observation of electrochemical,structural,and chemical evolution under realistic conditions,offering dynamic insights inaccessible to ex situ analyses.Here,a comprehensive review of in situ/operando characterization techniques is presented,focusing on the revelation of dynamic processes in lithium metal anodes,including first,real-time visualization approaches for monitoring lithium nucleation,growth,dissolution,and spatial distribution;second,chemical/structural/property probes for probing SEI formation,evolution,and related changes;third,trackers of active Li consumption for quantitative discrimination of lithium species and resolution of gas-release.The principles,applicability,and limitations of each method are systematically elucidated.Finally,the perspectives on current technical bottlenecks are provided,and a roadmap for future research is outlined,aiming to bridge the gap between fundamental studies and the practical engineering of high-energy-density lithium metal batteries.展开更多
This is a review on up-to-date in situ/operando methods for a comprehensive characterization of nano-porous materials.The group of nanoporous materials is constantly growing,and with it,the variety of possible applica...This is a review on up-to-date in situ/operando methods for a comprehensive characterization of nano-porous materials.The group of nanoporous materials is constantly growing,and with it,the variety of possible applications.Nanoporous materials include,among others,porous carbon materials,meso-porous silica,mesoporous transition metal oxides,zeolites,metal-organic frameworks(MOFs),or poly-mers.They are used as adsorbents,for gas storage,as catalysts,or for electrochemical applications to name just a few technical applications.Characterization of these materials has evolved from pure ex situ examination to increasingly complex in situ or operando methods.Monitoring nanoporous materials under reaction conditions allows for establishing structure-property relationships.This enables nanopor-ous materials to be adapted and optimized for specific processes.Recent developments on well-estab-lished but also exciting emerging methods for future applications will be discussed.The examples include in situ powder diffraction,total and small angle scattering,environmental electron microscopy,coupled with focused ion beam cutting,or X-ray tomography.This article will provide a useful reference to prac-titioners for in situ/operando characterization of nanoporous materials.展开更多
Accelerating the redox conversion of lithium polysulfides(Li PSs)with electrocatalysts has been regarded as an effective avenue to surmount the shuttle effect and realize high-performance lithium-sulfur(Li-S)batteries...Accelerating the redox conversion of lithium polysulfides(Li PSs)with electrocatalysts has been regarded as an effective avenue to surmount the shuttle effect and realize high-performance lithium-sulfur(Li-S)batteries.However,the complicated reaction process,especially the real-time evolution of sulfur-containing species and electrocatalysts under working conditions,has brought great difficulties in the explicit understanding of reaction mechanism of Li-S batteries,thereby severely hampering the design of highly efficient electrocatalysts.Therefore,a crucial prerequisite for correctly identifying the reaction mechanism is an in-depth analysis of the dynamic evolution of reaction intermediates and their structure-performance relationships.In this review,we comprehensively summarized the most recent progress in the dynamic behaviors of Li PSs and electrocatalysts of Li-S batteries under working conditions in conjunction with closely related in-situ/operando characterizations to recognize the realtime evolution of phase,composition,and atomic/electronic structure,thereby unraveling the corresponding catalytic mechanism.In addition,the major challenges and unexplored issues of catalytic conversion of Li PSs were summarized and discussed,aiming to provide perspectives into the development of highly efficient electrocatalysts in Li-S chemistry.Based on this review,we believe that reasonable regulation of reconstruction behaviors can achieve satisfactory electrocatalysts with high catalytic activity,accelerating the development of green energy.展开更多
The escalating global energy crisis,coupled with growing environmental concerns,has necessitated urgent advances in clean and efficient energy conversion technologies.Among the emerging approaches,electrocatalytic wat...The escalating global energy crisis,coupled with growing environmental concerns,has necessitated urgent advances in clean and efficient energy conversion technologies.Among the emerging approaches,electrocatalytic water splitting has garnered substantial interest as a carbonneutral strategy for hydrogen production,positioning hydrogen as a potential replacement for non-renewable fossil fuels[1].This process primarily involves two coupled half-reactions:the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER).In particular,the OER at the anode is hindered by intrinsically slow kinetics due to multi-electron transfer steps,electron-proton coupling,and adsorption/desorption processes.As a result,highly efficient electrocatalysts are required to reduce the overpotential.In this context,deciphering the actual catalytic sites and concomitant evolution of their electronic structure during OER under operando conditions have become a critical imperative.Such mechanistic insights establish structureproperty correlations that underpin the rational engineering of high-performance electrocatalysts.展开更多
Despite significant progress in fuel cell technology,its large-scale industrial application is still challenged by the frequently encountered performance failure during long-term operation.Clarifying the failure mecha...Despite significant progress in fuel cell technology,its large-scale industrial application is still challenged by the frequently encountered performance failure during long-term operation.Clarifying the failure mechanism is the key to extending the lifecycle and enhancing stability.Herein,we have developed a time and space resolved multi-field characterization,including electrochemical impedance spectroscopy,to unveil its underlying mechanism.With this operando and non-destructive characterization,the dynamic evolution of the internal mass transport,heat,and electricity field distribution is fully depicted within an industrial-scale fuel cell in operation.Thus,it is revealed that hydrogen starvation occurs in the outlet region due to the excessive hydrogen consumption during the loading-down process.This can induce local low current density and carbon corrosion,which may subsequently cause severe damage to the structure of the catalyst layer and membrane,ultimately leading to performance failure.With this understanding,we further identify a descriptor for early diagnosis to prevent any potential degradation.The methodology is of significance,which can bring fuel cell technology a step further towards industrial applications.展开更多
Situs inversus totalis(SIT)is a rare congenital anomaly in which the major organs are reversed from their normal positions.In patients with SIT,the right-lobe graft must be placed in the left upper quadrant(LUQ).Howev...Situs inversus totalis(SIT)is a rare congenital anomaly in which the major organs are reversed from their normal positions.In patients with SIT,the right-lobe graft must be placed in the left upper quadrant(LUQ).However,hepatic outflow obstruction is a critical issue,often requiring radiologic intervention because of compression or kinking following graft regeneration of the vessels[1–3].Therefore,preoperative planning is essential to address the challenges of graft placement and vein reconstruction.Despite these complexities,we previously reported techniques using a reversed modified right-lobe(mRL)graft from a donor in a conventional recipient with SIT[2].Here,we successfully applied a similar concept.展开更多
Optimizing the microchannel design of the next generation of chips requires an understanding of the in situ property evolution of the chip-based materials under fast cooling.This work overcomes the conventional relian...Optimizing the microchannel design of the next generation of chips requires an understanding of the in situ property evolution of the chip-based materials under fast cooling.This work overcomes the conventional reliance on reheating data of melt-quenched glasses by demonstrating direct observations of glass transition on cooling curves utilizing the most advanced fast differential scanning calorimetry.By leveraging an MEMS chip sensor that allows for rapid heat extraction from microgram-sized samples to a purged gas coolant,the device is able to reach ultra-fast cooling rates of up to 40,000 K·s^(−1).Four thermal regions are identified by examining the cooling behaviors of two metallic glasses.This is because the actual rate of the specimen can differ from the programmed rate,especially at high set rate when the actual rate decreases before the glass transition is completed.We define the operational window for reliable cooling curve analysis,build models with empirical and theoretical analyses to determine the maximum feasible cooling rate,and demonstrate how optimizing sample mass and environment temperature broaden this window.The method avoids deceptive structural relaxation effects verified by fictivetemperature analysis and permits the capture of full glass transition during cooling.展开更多
By means the in situ halogenation of the vinyl C-H bond in o-hydroxyphenyl enaminones,the step efficient synthesis of 3-diphenylphosphinyl chromones has been realized through the challenging construction of C-P(Ⅲ) bo...By means the in situ halogenation of the vinyl C-H bond in o-hydroxyphenyl enaminones,the step efficient synthesis of 3-diphenylphosphinyl chromones has been realized through the challenging construction of C-P(Ⅲ) bond by using diphenyl phosphine as reaction partner.In addition,the tunable synthesis of 2-phosphoryl chromanones has been achieved via hydrophosphorylation by simply modifying reaction conditions without using metal reagent.展开更多
Deep mining of natural resources,like coal,is increasingly utilizing directional blasting technology with slit charge for rock blasting at greater depths.This study,based on numerical simulation methods,analyzes the d...Deep mining of natural resources,like coal,is increasingly utilizing directional blasting technology with slit charge for rock blasting at greater depths.This study,based on numerical simulation methods,analyzes the dynamic behavior of slit charge blasting in three aspects:slit tube dynamic response,hoop stress evolution,and crack propagation.According to research findings,the failure mode of the slit tube mainly manifests as a tensile fracture of the inner wall and a shear fracture at the end connection,where the end connection of the slit tube is the weak point of the overall structure.The dynamic response of the slit tube mainly exhibits radial response in the vertical direction of the slit and hoop response in the slit direction.The hoop tensile stress plays a crucial role in determining the spread of cracks caused by explosions.As the in situ stress increases,the peak hoop tensile stress reduces,and the peak hoop compressive stress increases.This hinders the propagation of cracks.In addition,the directional impact is most pronounced in the middle of the borehole,with the longest primary directional crack observed.Conversely,the directional impact is least favorable near the bottom of the borehole.When the in situ stress reaches 60MPa,the purpose of directional fracture has not been achieved,suggesting combining presplit blasting for in situ stress relief to improve rock breaking efficiency.展开更多
Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance ...Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance relies on elucidating reaction mechanisms and structure-performance relationships via in situ studies.This review summarizes recent in situ studies of EECSTs through a variety of advanced characterization techniques aiming at mapping reaction pathways for the rational design of overall high-performance reaction systems.We outline the principles,capabilities,advantages,and limitations of various in situ techniques.Their applications in in situ studies of fuel cells,water/CO_(2)electrolysis,and lithium batteries are highlighted with representative examples.These studies enable dynamic tracking of chemical and structural evolution of overall reaction systems,including materials,intermediates,products,and surroundings during operation,providing insights critical to rational system design.Future advancements will involve integrating multimodal in situ/operando approaches with artificial intelligence to enable real-time monitoring at practical scales.Such integration promises precise mechanistic insights and robust structure-performance correlations,ultimately accelerating the development of high-performance EECSTs aligned with sustainability and market requirements.展开更多
The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesi...The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesis.Copper primarily exists as Cu^(+)and Cu^(2+)in hydrothermal solutions,with redox conditions governing their interconversion.In chloride-rich geological fluids,Cu-Cl complexes are considered critical for copper transport.However,the specific types and valence transitions of Cu-Cl complexes under varying hydrothermal conditions remain poorly understood.This study employed in situ Raman spectroscopy to systematically analyze Cu+HCl and CuCl_(2)+K_(2)S_(2)O_(3)/H_(2) systems under saturated vapor pressure at 25-300℃,elucidating the effects of temperature,Cl^(-)concentration,and redox conditions on copper speciation.In the Cu^(+)HCl system,copper dissolved as monovalent Cu-Cl complexes.At high temperatures(>200℃),[CuCl_(2)]^(-)is the dominated species,whereas[CuCl_(3)]^(2-)becomes prevalent at lower temperatures and higher HCl concentrations.For the Cu^(2+)-Cl system,the dominant species transitioned from[Cu(H_(2)O)n]^(2+)(<50℃)to[CuCl_(4)]^(2-)(100℃)and further to[CuCl]^(+)and[CuCl_(2)]^(0) at 300℃.The introduction of reducing agents(K_(2)S_(2)O_(3)/H_(2))facilitated Cu^(2+)→Cu^(+)reduction,thereby stabilizing Cu^(+)-Cl complexes and inducing partial copper precipitation.The behavior of copper in chloriderich hydrothermal fluids observed in this study indicates that high-temperature oxidizing fluids facilitate Cu mobilization,while cooling and redox changes promote deposition and ore minerals formation.展开更多
基金the financial support of the National Natural Science Foundation of China(Nos.12172206 and 11972218)。
文摘Lithium metal batteries(LMBs)represent a promising solution for next-generation energy storage due to their high energy density,but the growth of lithium dendrites presents significant challenges to their performance and safety.This review provides a comprehensive overview of the mechanisms behind lithium dendrite formation and the role of in situ/operando observation and phase field simulation in understanding and mitigating this issue,The key driving factors of dendrite growth,such as lithium-ion flux heterogeneity,surface defects,and localized stress,are explored through advanced experimental techniques,which enable real-time visualization of dendrite nucleation and growth dynamics.Complementarily,phase field simulations provide insights into subsurface and temporal evolution of dendrites by modeling thermodynamic and kinetic processes,while machine learning techniques optimize simulation accuracy through data-driven parameter refinement.The integration of experimental observations with simulation models holds great potential in improving understanding and predictive capabilities.Despite ongoing progress,challenges remain in resolving technical limitations in observation techniques,improving computational efficiency,and fostering interdisciplinary collaboration.This review highlights the synergy between experimental and computational strategies in advancing the development of LMBs and calls for continued research to overcome existing hurdles and unlock the full potential of lithium metal anodes.
基金financially supported by the National Natural Science Foundation of China (22350410386,W2412116,22375200,U22A202175,21961142006)。
文摘Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm.
基金funded by the EU H2020 Marie Skłodowska-Curie Fellowship (1439425)the National Natural Science Foundation of China (No. 52171199 and 22479011)
文摘Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research.
基金financially supported by the National Key R&D Program of China(2016YFB0100100)the National Natural Science Foundation of China(Nos.21433013,U1832218)the support from China Scholarship Council
文摘The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue.Herein,we employed in situ/operando X-ray absorption spectroscopy(XAS)to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces,respectively,in a real-time condition.After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix(BSOC),we found the Li/S cell showed greatly improved sulfur utilization and longer life span.The operando S Kedge XAS results revealed that the BSOC modification was bi-functional:trapping polysulfides and catalyzing conversion of sulfur species simultaneously.We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection.Our results could offer potential stratagem for designing more advanced Li/S cells.
基金supported as part of the Joint Center for Energy Storage Research(JCESR)an Energy Innovation Hub funded by the U.S.Department of Energy(DOE),Office of Science,Basic Energy Sciences
文摘The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and good charge efficiency.However,due to safety concerns,the depletion of lithium reserves,and the corresponding increase of cost,an alternative battery system becomes more and more desirable.To develop alternative battery systems with low cost and high material abundance,for example,sodium,magnesium,zinc,and calcium,it is important to understand the chemical and electronic structure of materials.Soft X-ray spectroscopy,for example,X-ray absorption spectroscopy(XAS),X-ray emission spectroscopy(XES),and resonant inelastic soft X-ray scattering(RIXS),is an element-specific technique with sensitivity to the local chemical environment and structural order of the element of interest.Modern soft X-ray systems enable operando experiments that can be applied to amorphous and crystalline samples,making it a powerful tool for studying the electronic and structural changes in electrode and electrolyte species.In this article,the application of in situ/operando(soft)X-ray spectroscopy in beyond lithium-ion batteries is reviewed to demonstrate how such spectroscopic characterizations could facilitate the interpretation of interfacial phenomena under in situ/operando condition and subsequent development of the beyond lithium-ion batteries.
基金supported by the Natural Science Foundation of Jiangsu Province,China(BK20170630)the National Natural Science Foundation of China(51802149 and U1801251)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Nanjing University Technology Innovation Fund Project。
文摘Nowadays,in-situ/operando characterization becomes one of the most powerful as well as available means to monitor intricate reactions and investigate energy-storage mechanisms within advanced batteries.The new applications and novel devices constructed in recent years are necessary to be reviewed for inspiring subsequent studies.Hence,we summarize the progress of in-situ/operando techniques employed in rechargeable batteries.The members of this large family are divided into three sections for introduction,including bulk material,electrolyte/electrode interface and gas evolution.In each part,various energy-storage systems are mentioned and the related experimental details as well as data analysis are discussed.The simultaneous strategies of various in-situ methods are highlighted as well.Finally,current challenges and potential solutions are concluded towards the rising influence and enlarged appliance of in-situ/operando techniques in the battery research.
基金support from Natural Science Foundation of Jiangsu Province (grant number BK20211507)National Natural Science Foundation of China (grant number 61774080)the start-up funds from Changzhou University。
文摘The increasing demands of multifunctional organic electronics require advanced organic semiconducting materials to be developed and significant improvements to be made to device performance. Thus, it is necessary to gain an in-depth understanding of the film growth process, electronic states, and dynamic structure-property relationship under realistic operation conditions, which can be obtained by in-situ/operando characterization techniques for organic devices. Here, the up-todate developments in the in-situ/operando optical, scanning probe microscopy, and spectroscopy techniques that are employed for studies of film morphological evolution, crystal structures, semiconductor-electrolyte interface properties, and charge carrier dynamics are described and summarized. These advanced technologies leverage the traditional static characterizations into an in-situ and interactive manipulation of organic semiconducting films and devices without sacrificing the resolution, which facilitates the exploration of the intrinsic structure-property relationship of organic materials and the optimization of organic devices for advanced applications.
基金financed by the National Natural Science Foundation of China(No.22202169)Xuzhou Science and Technology Plan Project of China(No.KC21294)。
文摘Catalysts can significantly promote the reaction dynamics and are therefore considered crucial components for achieving high electrochemical energy conversion efficiency.However,the active sites of the catalysts,particularly for nano-level and atomic-level catalysts commonly undergo reconstruction under practical applications.Therefore,obtaining an in-depth and systematic understanding on the real active sites through in situ/operando characterization techniques is a prerequisite for establishing the structureperformance relationship and guiding the future design of more efficient electrocatalysts.Herein,we summarize the recent progress of in situ/operando characterization techniques for identifying the nature of active sites of electrocatalysts when used in electrocatalytic energy conversion reaction.Specifically,our focus lies in the fundamental principles of various in situ/operando characterization techniques,with particular emphasis on their applications for electrocatalytic reactions.Beyond that,the challenges and perspective insights are also added in the final section to highlight the future direction of this important field.
文摘Lithium metal anodes,with high theoretical capacity and low reduction potential,are widely regarded as the ideal solution to overcome the energy-density limits of current batteries.However,uncontrolled Li dendrite growth,repeated rupture and reconstruction of solid electrolyte interphase(SEI),and irreversible side reactions severely impede their commercial viability.A deep understanding of these complex failure mechanisms and their intrinsic links to electrochemical performance is essential to surmount these challenges.Conventional ex situ techniques only provide static snapshots and may distort transient information.In contrast,in situ/operando characterization enables real-time observation of electrochemical,structural,and chemical evolution under realistic conditions,offering dynamic insights inaccessible to ex situ analyses.Here,a comprehensive review of in situ/operando characterization techniques is presented,focusing on the revelation of dynamic processes in lithium metal anodes,including first,real-time visualization approaches for monitoring lithium nucleation,growth,dissolution,and spatial distribution;second,chemical/structural/property probes for probing SEI formation,evolution,and related changes;third,trackers of active Li consumption for quantitative discrimination of lithium species and resolution of gas-release.The principles,applicability,and limitations of each method are systematically elucidated.Finally,the perspectives on current technical bottlenecks are provided,and a roadmap for future research is outlined,aiming to bridge the gap between fundamental studies and the practical engineering of high-energy-density lithium metal batteries.
文摘This is a review on up-to-date in situ/operando methods for a comprehensive characterization of nano-porous materials.The group of nanoporous materials is constantly growing,and with it,the variety of possible applications.Nanoporous materials include,among others,porous carbon materials,meso-porous silica,mesoporous transition metal oxides,zeolites,metal-organic frameworks(MOFs),or poly-mers.They are used as adsorbents,for gas storage,as catalysts,or for electrochemical applications to name just a few technical applications.Characterization of these materials has evolved from pure ex situ examination to increasingly complex in situ or operando methods.Monitoring nanoporous materials under reaction conditions allows for establishing structure-property relationships.This enables nanopor-ous materials to be adapted and optimized for specific processes.Recent developments on well-estab-lished but also exciting emerging methods for future applications will be discussed.The examples include in situ powder diffraction,total and small angle scattering,environmental electron microscopy,coupled with focused ion beam cutting,or X-ray tomography.This article will provide a useful reference to prac-titioners for in situ/operando characterization of nanoporous materials.
基金supported by the National Natural Science Foundation of China(22309019,12275189,22472111,and 11832007)the Natural Science Foundation of Sichuan Province(2023NSFSC1130)+1 种基金the Sichuan Province Support Tianfu Distinguished Scientist Program(126608533369)the Suzhou Science and Technology Project Prospective Application Research Program(SYG202109)。
文摘Accelerating the redox conversion of lithium polysulfides(Li PSs)with electrocatalysts has been regarded as an effective avenue to surmount the shuttle effect and realize high-performance lithium-sulfur(Li-S)batteries.However,the complicated reaction process,especially the real-time evolution of sulfur-containing species and electrocatalysts under working conditions,has brought great difficulties in the explicit understanding of reaction mechanism of Li-S batteries,thereby severely hampering the design of highly efficient electrocatalysts.Therefore,a crucial prerequisite for correctly identifying the reaction mechanism is an in-depth analysis of the dynamic evolution of reaction intermediates and their structure-performance relationships.In this review,we comprehensively summarized the most recent progress in the dynamic behaviors of Li PSs and electrocatalysts of Li-S batteries under working conditions in conjunction with closely related in-situ/operando characterizations to recognize the realtime evolution of phase,composition,and atomic/electronic structure,thereby unraveling the corresponding catalytic mechanism.In addition,the major challenges and unexplored issues of catalytic conversion of Li PSs were summarized and discussed,aiming to provide perspectives into the development of highly efficient electrocatalysts in Li-S chemistry.Based on this review,we believe that reasonable regulation of reconstruction behaviors can achieve satisfactory electrocatalysts with high catalytic activity,accelerating the development of green energy.
基金supported by the National Natural Science Foundation of China(Grant No.22368020)the Research Foundation for Talented Scholars of Hainan University,China(No.RZ2300002666).
文摘The escalating global energy crisis,coupled with growing environmental concerns,has necessitated urgent advances in clean and efficient energy conversion technologies.Among the emerging approaches,electrocatalytic water splitting has garnered substantial interest as a carbonneutral strategy for hydrogen production,positioning hydrogen as a potential replacement for non-renewable fossil fuels[1].This process primarily involves two coupled half-reactions:the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER).In particular,the OER at the anode is hindered by intrinsically slow kinetics due to multi-electron transfer steps,electron-proton coupling,and adsorption/desorption processes.As a result,highly efficient electrocatalysts are required to reduce the overpotential.In this context,deciphering the actual catalytic sites and concomitant evolution of their electronic structure during OER under operando conditions have become a critical imperative.Such mechanistic insights establish structureproperty correlations that underpin the rational engineering of high-performance electrocatalysts.
基金supported by the National Key R&D Program of China[2023YFB4006100]。
文摘Despite significant progress in fuel cell technology,its large-scale industrial application is still challenged by the frequently encountered performance failure during long-term operation.Clarifying the failure mechanism is the key to extending the lifecycle and enhancing stability.Herein,we have developed a time and space resolved multi-field characterization,including electrochemical impedance spectroscopy,to unveil its underlying mechanism.With this operando and non-destructive characterization,the dynamic evolution of the internal mass transport,heat,and electricity field distribution is fully depicted within an industrial-scale fuel cell in operation.Thus,it is revealed that hydrogen starvation occurs in the outlet region due to the excessive hydrogen consumption during the loading-down process.This can induce local low current density and carbon corrosion,which may subsequently cause severe damage to the structure of the catalyst layer and membrane,ultimately leading to performance failure.With this understanding,we further identify a descriptor for early diagnosis to prevent any potential degradation.The methodology is of significance,which can bring fuel cell technology a step further towards industrial applications.
文摘Situs inversus totalis(SIT)is a rare congenital anomaly in which the major organs are reversed from their normal positions.In patients with SIT,the right-lobe graft must be placed in the left upper quadrant(LUQ).However,hepatic outflow obstruction is a critical issue,often requiring radiologic intervention because of compression or kinking following graft regeneration of the vessels[1–3].Therefore,preoperative planning is essential to address the challenges of graft placement and vein reconstruction.Despite these complexities,we previously reported techniques using a reversed modified right-lobe(mRL)graft from a donor in a conventional recipient with SIT[2].Here,we successfully applied a similar concept.
基金supported by the National Natural Science Foundation of China (Grant Nos.92580120 and 52471188)。
文摘Optimizing the microchannel design of the next generation of chips requires an understanding of the in situ property evolution of the chip-based materials under fast cooling.This work overcomes the conventional reliance on reheating data of melt-quenched glasses by demonstrating direct observations of glass transition on cooling curves utilizing the most advanced fast differential scanning calorimetry.By leveraging an MEMS chip sensor that allows for rapid heat extraction from microgram-sized samples to a purged gas coolant,the device is able to reach ultra-fast cooling rates of up to 40,000 K·s^(−1).Four thermal regions are identified by examining the cooling behaviors of two metallic glasses.This is because the actual rate of the specimen can differ from the programmed rate,especially at high set rate when the actual rate decreases before the glass transition is completed.We define the operational window for reliable cooling curve analysis,build models with empirical and theoretical analyses to determine the maximum feasible cooling rate,and demonstrate how optimizing sample mass and environment temperature broaden this window.The method avoids deceptive structural relaxation effects verified by fictivetemperature analysis and permits the capture of full glass transition during cooling.
基金financially supported by the National Natural Science Foundation of China (No.22261026)。
文摘By means the in situ halogenation of the vinyl C-H bond in o-hydroxyphenyl enaminones,the step efficient synthesis of 3-diphenylphosphinyl chromones has been realized through the challenging construction of C-P(Ⅲ) bond by using diphenyl phosphine as reaction partner.In addition,the tunable synthesis of 2-phosphoryl chromanones has been achieved via hydrophosphorylation by simply modifying reaction conditions without using metal reagent.
基金National Natural Science Foundation of China,Grant/Award Numbers:52204085,52227805。
文摘Deep mining of natural resources,like coal,is increasingly utilizing directional blasting technology with slit charge for rock blasting at greater depths.This study,based on numerical simulation methods,analyzes the dynamic behavior of slit charge blasting in three aspects:slit tube dynamic response,hoop stress evolution,and crack propagation.According to research findings,the failure mode of the slit tube mainly manifests as a tensile fracture of the inner wall and a shear fracture at the end connection,where the end connection of the slit tube is the weak point of the overall structure.The dynamic response of the slit tube mainly exhibits radial response in the vertical direction of the slit and hoop response in the slit direction.The hoop tensile stress plays a crucial role in determining the spread of cracks caused by explosions.As the in situ stress increases,the peak hoop tensile stress reduces,and the peak hoop compressive stress increases.This hinders the propagation of cracks.In addition,the directional impact is most pronounced in the middle of the borehole,with the longest primary directional crack observed.Conversely,the directional impact is least favorable near the bottom of the borehole.When the in situ stress reaches 60MPa,the purpose of directional fracture has not been achieved,suggesting combining presplit blasting for in situ stress relief to improve rock breaking efficiency.
基金supported by the National Key Research and Development Program of China(2023YFA1508004)the National Natural Science Foundation of China(T2293692,22502164,92472203,22222903,52271229,22472074,22272069,22361132532,and 22021001)+6 种基金the Industry-University-Research Joint Innovation Project of Fujian Province(2023H6029)the Beijing National Laboratory for Molecular Sciences(BNLMS202305)the Scientific and Technological Project of Yunnan Precious Metals Laboratory(YPML-20240502063)the Liaoning Binhai Laboratory(Grant No.2024-05)the State Key Laboratory of Fine Chemicals,Dalian University of Technology(KF 2401)the Postdoctoral Fellowship Program of CPSF under Grant Number GZC20240897the China Postdoctoral Science Foundation(No.2025M770016).
文摘Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance relies on elucidating reaction mechanisms and structure-performance relationships via in situ studies.This review summarizes recent in situ studies of EECSTs through a variety of advanced characterization techniques aiming at mapping reaction pathways for the rational design of overall high-performance reaction systems.We outline the principles,capabilities,advantages,and limitations of various in situ techniques.Their applications in in situ studies of fuel cells,water/CO_(2)electrolysis,and lithium batteries are highlighted with representative examples.These studies enable dynamic tracking of chemical and structural evolution of overall reaction systems,including materials,intermediates,products,and surroundings during operation,providing insights critical to rational system design.Future advancements will involve integrating multimodal in situ/operando approaches with artificial intelligence to enable real-time monitoring at practical scales.Such integration promises precise mechanistic insights and robust structure-performance correlations,ultimately accelerating the development of high-performance EECSTs aligned with sustainability and market requirements.
基金jointly funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(grant No.XDA0430301)the National Natural Science Foundation of China(grant Nos.42130109,41973059)。
文摘The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesis.Copper primarily exists as Cu^(+)and Cu^(2+)in hydrothermal solutions,with redox conditions governing their interconversion.In chloride-rich geological fluids,Cu-Cl complexes are considered critical for copper transport.However,the specific types and valence transitions of Cu-Cl complexes under varying hydrothermal conditions remain poorly understood.This study employed in situ Raman spectroscopy to systematically analyze Cu+HCl and CuCl_(2)+K_(2)S_(2)O_(3)/H_(2) systems under saturated vapor pressure at 25-300℃,elucidating the effects of temperature,Cl^(-)concentration,and redox conditions on copper speciation.In the Cu^(+)HCl system,copper dissolved as monovalent Cu-Cl complexes.At high temperatures(>200℃),[CuCl_(2)]^(-)is the dominated species,whereas[CuCl_(3)]^(2-)becomes prevalent at lower temperatures and higher HCl concentrations.For the Cu^(2+)-Cl system,the dominant species transitioned from[Cu(H_(2)O)n]^(2+)(<50℃)to[CuCl_(4)]^(2-)(100℃)and further to[CuCl]^(+)and[CuCl_(2)]^(0) at 300℃.The introduction of reducing agents(K_(2)S_(2)O_(3)/H_(2))facilitated Cu^(2+)→Cu^(+)reduction,thereby stabilizing Cu^(+)-Cl complexes and inducing partial copper precipitation.The behavior of copper in chloriderich hydrothermal fluids observed in this study indicates that high-temperature oxidizing fluids facilitate Cu mobilization,while cooling and redox changes promote deposition and ore minerals formation.
