Proton-exchange membrane fuel cell and water electrolyzer(PEMFC and PEMWE)with high conversion efficiency and zero-carbon emission stand out as an attractive strategy for efficient conversion between hydrogen energy a...Proton-exchange membrane fuel cell and water electrolyzer(PEMFC and PEMWE)with high conversion efficiency and zero-carbon emission stand out as an attractive strategy for efficient conversion between hydrogen energy and renewable electricity.As a key component,efficient oxygen electrocatalyst for promoting sluggish reaction kinetics of oxygen reduction and evolution reaction(ORR and OER)under harsh operation conditions severely limited progress of these devices.Among various candidates,Ptgroup(Pt,Ir,and Ru)-based electrocatalysts are still the most active ORR/OER catalysts.However,the scarcity,high cost,and questionable stability restrict the widespread applications and the commercialization of PEMWE/PEMFC.Progresses in synthesizing atomically dispersed single/multiple-atom catalysts(SACs/MACs)offer new opportunities to Pt-group ORR/OER catalysts owing to nearly 100% metal utilization and high catalytic activities.Extensive efforts have been continuously devoted to optimizing the local structure of Pt-group OER/ORR catalysts at atom-level for further enhancing stability and activity.In this review,universal synthesis methods to prepare Ptgroup SACs are discussed first,highlighting crucial factors which affect the structure and catalytic performance.Afterward,advanced characterization techniques for directly confirming atomic dispersed metal atoms were introduced,including aberration-corrected high-angle-annular-dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy.Importantly,considerations for rational catalyst design and typical Pt-group SACs/MACs are summarized regarding the regulation strategy of atomically dispersed metal sites and various supports,and effects of metal-support interaction on the catalytic performance.Finally,key challenges and proposed perspectives for future development of atomically dispersed Pt-group oxygen electrocatalysts for fuel cell and electrolyzer are briefly discussed.展开更多
The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis,with anion-exchange membrane water electrolyzers(AEMWEs)emerging as a cost-effective alternative by combin...The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis,with anion-exchange membrane water electrolyzers(AEMWEs)emerging as a cost-effective alternative by combining the merits of alkaline water electrolyzers(AWEs)and proton-exchange membrane water electrolyzers(PEMWEs).However,challenges persist in membrane stability,oxygen evolution reaction(OER)kinetics,and mass transport efficiency.This review highlights the pivotal role of transition metal-based layered double hydroxides(LDHs)as high-performance,non-precious OER catalysts for AEMWEs,emphasizing their tunable electronic structures,abundant active sites,and alkaline stability.We systematically outline LDHs synthesis strategies(top-down/bottom-up approaches,and self-supporting LDHs engineering on the conductive substrates),and AEMWE component design,including membraneelectrode assembly optimization and ionomer-free architectures.Standardized evaluation protocols-short-circuit inspection,impedance spectroscopy,and durability assessment are detailed to benchmark performance.Moreover,recent advances in LDHs modification(cation/anion doping,heterojunction design,three-dimensional(3D)electrode structuring)are discussed for alkaline-fed systems,alongside emerging applications in seawater and pure-water electrolysis.By correlating material innovations with device-level metrics,this work provides a roadmap to address scalability challenges,offering perspectives on advancing AEMWEs for sustainable,large-scale hydrogen production.展开更多
Proton Exchange Membrane Water Electrolyzers(PEMWE)are efficient and sustainable hydrogen production devices.This article analyzes their static and dynamic electrical models integrated with degradation mechanisms.Stat...Proton Exchange Membrane Water Electrolyzers(PEMWE)are efficient and sustainable hydrogen production devices.This article analyzes their static and dynamic electrical models integrated with degradation mechanisms.Static models reveal steady-state behavior,while dynamic models capture transient responses to input variations.The developed modeling approach combines the activation and diffusion phenomena,resulting in a novel PEMWE model that closely reflects real-world conditions and enables fast simulations.The electrical model is integrated with the aging model through two key ratios,surface degradation ratio and membrane degradation ratio,which characterize degradation mechanisms affecting electrode and membrane performance.The linear model using second-order Taylor approximation enables the development of a diagnosis approach that can contribute to estimating the remaining useful life of PEMWEs.By associating aging models with electrical models through the proposed ratios,a deeper understanding is achieved regarding how degra-dation phenomena evolve and influence electrolyzer efficiency and durability.The integrated framework enables predictive maintenance strategies,making it valuable for industrial hydrogen production applications.展开更多
Designing efficient and durable hydrogen evolution reaction(HER)catalysts for seawater electrolysis is crucial for large-scale hydrogen production.Here,we introduce a theory-driven design of metal/WN electrocatalysts,...Designing efficient and durable hydrogen evolution reaction(HER)catalysts for seawater electrolysis is crucial for large-scale hydrogen production.Here,we introduce a theory-driven design of metal/WN electrocatalysts,with metal strongly coupled to lattice-matched WN.Theoretical calculations for Pt/WN reveal that W sites enhance H_(2)O adsorption/dissociation,optimizing Pt's H binding.The prepared Pt/WN@CP nanorods can catalyze HER with low overpotentials of 107 and 113 mV at 500 mA cm^(-2)in alkaline water/seawater,respectively,surpassing Pt/C.Extended calculations and experiments show that the optimized Ni/WN@CP-90 achieves an optimal ΔG_(H*)and overpotential of 219 mV at 500 mA cm^(-2)in alkaline seawater,demonstrating the versatility of the WN support to promote HER activity.Notably,the anion exchange membrane water electrolyzer(AEMWE)constructed by Pt/WN@CP or Ni/WN@CP-90 with NiFe-LDH@NF demonstrates outstanding hydrogen production activity with excellent Faraday efficiency(~100%)and durability(120 h),indicating the potential application of WN-supported catalysts for efficient and stable seawater electrolysis.展开更多
Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen (H_(2)) and electricity.However,the design and development of such systems ...Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen (H_(2)) and electricity.However,the design and development of such systems is still in its infancy.Herein,an integrated hydrogen-oxygen (O_(2))-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate (NaNiHCF) and Zn^(2+)/Zn as dual redox electrodes.The decoupled electrolyzer enables to produce H_(2)and O_(2)in different time and space with almost 100%Faradaic efficiency at 100 mA cm^(-2).Then,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A cm^(-2).By connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.展开更多
Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO_(2)emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO_(2)usi...Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO_(2)emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO_(2)using alkaline solutions with reactive absorption.In this work,we present a CO_(2)-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm^(2)electrode area.Our electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended periods.The techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.展开更多
Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave redu...Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave reduction and low-temperature phosphorization strategy to synthesize a highly efficient HER catalyst,comprising P,N-codoped carbon-supported RuP_(2)nanocluster(RuP_(2)@PNC).RuP_(2)@PNC demonstrates outstanding HER performance,achieving overpotentials of 18 and 44 mV at a current density of 10 mA cm^(-2)in alkaline and acidic media,respectively.Furthermore,an AEMWE device utilizing RuP_(2)@PNC as the cathode catalyst delivers a current density of 0.5 A cm^(-2)at a cell voltage of 1.84 V and exhibits remarkable stability over 150 h of operation.Experimental analyses and density functional theory(DFT)calculations reveal that the synergistic effects of P,N-codoped and the unique structure of RuP_(2)enhance electron transfer between Ru and the support,optimize the electronic structure,and regulate the d–band center of Ru.These features improve water adsorption,weaken the Ru–H binding strength,and facilitate efficient H_(2)desorption,collectively driving the superior HER activity of RuP_(2)@PNC.This work offers an effective design strategy for high-performance HER catalysts and provides valuable insights for accelerating the development of AEMWE technology.展开更多
The state-of-the-art anion-exchange membrane water electrolyzers(AEMWEs)require highly stable electrodes for prolonged operation.The stability of the electrode is closely linked to the effective evacuation of H_(2) or...The state-of-the-art anion-exchange membrane water electrolyzers(AEMWEs)require highly stable electrodes for prolonged operation.The stability of the electrode is closely linked to the effective evacuation of H_(2) or O_(2) gas generated from electrode surface during the electrolysis.In this study,we prepared a superhydrophilic electrode by depositing porous nickel–iron nanoparticles on annealed TiO_(2) nanotubes(NiFe/ATNT)for rapid outgassing of such nonpolar gases.The super-hydrophilic NiFe/ATNT electrode exhibited an overpotential of 235 mV at 10 mA cm^(−2) for oxygen evolution reaction in 1.0 M KOH solution,and was utilized as the anode in the AEMWE to achieve a current density of 1.67 A cm^(−2) at 1.80 V.In addition,the AEMWE with NiFe/ATNT electrode,which enables effective outgassing,showed record stability for 1500 h at 0.50 A cm^(−2) under harsh temperature conditions of 80±3℃.展开更多
Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This...Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This review explores multi-scale modeling as a tool to visualize multi-phase flow and improve mass transport in water electrolyzers.At the nanoscale,molecular dynamics(MD)simulations reveal how electrode surface features and wettability influence nanobubble nucleation and stability.Moving to the mesoscale,models such as volume of fluid(VOF)and lattice Boltzmann method(LBM)shed light on bubble transport in porous transport layers(PTLs).These insights inform innovative designs,including gradient porosity and hydrophilic-hydrophobic patterning,aimed at minimizing gas saturation.At the macroscale,VOF simulations elucidate two-phase flow regimes within channels,showing how flow field geometry and wettability affect bubble discharging.Moreover,artificial intelligence(AI)-driven surrogate models expedite the optimization process,allowing for rapid exploration of structural parameters in channel-rib flow fields and porous flow field designs.By integrating these approaches,we can bridge theoretical insights with experimental validation,ultimately enhancing water electrolyzer performance,reducing costs,and advancing affordable,high-efficiency hydrogen production.展开更多
Proton exchange membrane water electrolysis(PEMWE)technology is widely recognized as a cornerstone for green hydrogen production,offering high operational current densities exceeding 1.0 A cm^(-2),rapid dynamic respon...Proton exchange membrane water electrolysis(PEMWE)technology is widely recognized as a cornerstone for green hydrogen production,offering high operational current densities exceeding 1.0 A cm^(-2),rapid dynamic response capabilities,and zero-carbon emission characteristics[1].However,the sluggish kinetics of oxygen evolution reaction(OER)at the anode presents a critical bottleneck for large-scale commercial deployment(Fig.1(a)).Despite significant advancements through electronic structure modulation[2]and coordination environment optimization[3],the deprotonation energy barrier of oxygen-containing intermediates and the stability of active sites under acidic conditions remain unresolved challenges.展开更多
Creating strongly coupled heterostructures with favorable catalytic activities is crucial for promoting the performance of catalytic reactions,especially those involve multiple intermediates.Herein,we fabricated a str...Creating strongly coupled heterostructures with favorable catalytic activities is crucial for promoting the performance of catalytic reactions,especially those involve multiple intermediates.Herein,we fabricated a strongly coupled platinum/molybdenum nitrides nanocluster heterostructure on nitrogen-doped reduced graphene oxide(Pt/Mo_(2)N-NrGO)for alkaline hydrogen evolution reaction.The well-defined Pt-containing Anderson-type polyoxometalates promote strong interfacial Pt-N-Mo bonding in Pt/Mo_(2)N-NrGO,which exhibits a remarkably low overpotential,high mass activity,and exceptional long-term durability(>500 h at 1500 mA cm^(-2))in an anion-exchange membrane water electrolyzer(AEMWE).Operando Raman spectroscopy and density functional theory reveal that pronounced electronic coupling at the Pt/Mo_(2)N cluster interface facilitates the catalytic decomposition of H_(2)O through synergistic stabilization of intermediates(Pt-H^(*)and Mo-OH^(*)),thereby enhancing the kinetics of the rate-determining Volmer step.Techno-economic analysis indicates a levelized hydrogen production cost of$2.02 kg^(-1),meeting the US DOE targets.Our strategy presents a viable pathway to designing next-generation catalysts for industrial AEMWE for green hydrogen production.展开更多
Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surfa...Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surface is covered with water, there is inadequacy of freshwater in most parts of the world. Hence, splitting seawater instead of freshwater could be a truly sustainable alternative. However, direct seawater splitting faces challenges because of the complex composition of seawater. The composition, and hence, the local chemistry of seawater may vary depending on its origin, and in most cases, tracking of the side reactions and standardizing and customizing the catalytic process will be an extra challenge. The corrosion of catalysts and competitive side reactions due to the presence of various inorganic and organic pollutants create challenges for developing stable electro-catalysts. Hence, seawater splitting generally involves a two-step process, i.e., purification of seawater using reverse osmosis and then subsequent fresh water splitting. However, this demands two separate chambers and larger space, and increases complexity of the reactor design. Recently, there have been efforts to directly split seawater without the reverse osmosis step. Herein, we represent the most recent innovative approaches to avoid the two-step process, and compare the potential application of membrane-assisted and membrane-less electrolyzers in direct seawater splitting(DSS). We particularly discuss the device engineering, and propose a novel electrolyzer design strategies for concentration gradient based membrane-less microfluidic electrolyzer.展开更多
CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at desi...CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at design and understanding of catalytic materials and electrolyte systems,the CO_(2) ER performance(such as current density,selectivity,stability,CO_(2) conversion,etc.)has been continually increased.Unfortunately,there has been relatively little attention paid to the large-scale CO 2 electrolyzers,which stand just as one obstacle,alongside series-parallel integration,challenging the practical application of this infant technology.In this review,the latest progress on the structures of low-temperature CO_(2) electrolyzers and scale-up studies was systematically overviewed.The influence of the CO_(2) electrolyzer configurations,such as the flow channel design,gas diffusion electrode(GDE)and ion exchange membrane(IEM),on the CO_(2) ER performance was further discussed.The review could provide inspiration for the design of large-scale CO_(2) electrolyzers so as to accelerate the industrial application of CO_(2) ER technology.展开更多
An effective oxygen evolution electrode with Ir0.6Sn0.4O2 was designed for proton exchange membrane(PEM)water electrolyzers.The anode catalyst layer exhibits a jagged structure with smaller particles and pores,which p...An effective oxygen evolution electrode with Ir0.6Sn0.4O2 was designed for proton exchange membrane(PEM)water electrolyzers.The anode catalyst layer exhibits a jagged structure with smaller particles and pores,which provide more active sites and mass transportation channels.The prepared IrSn electrode showed a cell voltage of 1.96 V at 2.0 A cm^-2 with Ir loading as low as 0.294 mg cm^-2.Furthermore,Ir Sn electrode with different anode catalyst loadings was investigated.The IrS n electrode indicates higher mass current and more stable cell voltage than the commercial Ir Black electrode at low loading.展开更多
Anion exchange membrane(AEM)electrolysis is a promising membrane-based green hydrogen production technology.However,AEM electrolysis still remains in its infancy,and the performance of AEM electrolyzers is far behind ...Anion exchange membrane(AEM)electrolysis is a promising membrane-based green hydrogen production technology.However,AEM electrolysis still remains in its infancy,and the performance of AEM electrolyzers is far behind that of well-developed alkaline and proton exchange membrane electrolyzers.Therefore,breaking through the technical barriers of AEM electrolyzers is critical.On the basis of the analysis of the electrochemical performance tested in a single cell,electrochemical impedance spectroscopy,and the number of active sites,we evaluated the main technical factors that affect AEM electrolyzers.These factors included catalyst layer manufacturing(e.g.,catalyst,carbon black,and anionic ionomer)loadings,membrane electrode assembly,and testing conditions(e.g.,the KOH concentration in the electrolyte,electrolyte feeding mode,and operating temperature).The underlying mechanisms of the effects of these factors on AEM electrolyzer performance were also revealed.The irreversible voltage loss in the AEM electrolyzer was concluded to be mainly associated with the kinetics of the electrode reaction and the transport of electrons,ions,and gas-phase products involved in electrolysis.Based on the study results,the performance and stability of AEM electrolyzers were significantly improved.展开更多
Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)ar...Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and compactness.Bipolar plates account for a relatively high percentage of the total cost and weight compared with other components of PEMWEs.Thus,optimization of their design may accelerate the promotion of PEMWEs.This paper reviews the advances in materials and flow-field design for bipolar plates.First,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and potential.Then,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are presented.Furthermore,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are explored.Finally,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science.展开更多
Alkaline water electrolysis(AWE)is the most mature technology for hydrogen production by water electrolysis.Alkaline water electrolyzer consists of multiple electrolysis cells,and a single cell consists of a diaphragm...Alkaline water electrolysis(AWE)is the most mature technology for hydrogen production by water electrolysis.Alkaline water electrolyzer consists of multiple electrolysis cells,and a single cell consists of a diaphragm,electrodes,bipolar plates and end plates,etc.The existing industrial bipolar plate channel is concave-convex structure,which is manufactured by complicated and high-cost mold punching.This structure still results in uneven electrolyte flow and low current density in the electrolytic cell,further increasing in energy consumption and cost of AWE.Thereby,in this article,the electrochemical and flow model is firstly constructed,based on the existing industrial concave and convex flow channel structure of bipolar plate,to study the current density,electrolyte flow and bubble distribution in the electrolysis cell.The reliability of the model was verified by comparison with experimental data in literature.Among which,the electrochemical current density affects the bubble yield,on the other hand,the generated bubbles cover the electrode surface,affecting the active specific surface area and ohmic resistance,which in turn affects the electrochemical reaction.The result indicates that the flow velocity near the bottom of the concave ball approaches zero,while the flow velocity on the convex ball surface is significantly higher.Additionally,vortices are observed within the flow channel structure,leading to an uneven distribution of electrolyte.Next,modelling is used to optimize the bipolar plate structure of AWE by simulating the electrochemistry and fluid flow performances of four kinds of structures,namely,concave and convex,rhombus,wedge and expanded mesh,in the bipolar plate of alkaline water electrolyzer.The results show that the expanded mesh channel structure has the largest current density of 3330 A/m^(2)and electrolyte flow velocity of 0.507 m/s in the electrolytic cell.Under the same current density,the electrolytic cell with the expanded mesh runner structure has the smallest potential and energy consumption.This work provides a useful guide for the comprehensive understanding and optimization of channel structures,and a theoretical basis for the design of large-scale electrolyzer.展开更多
Proton exchange membrane(PEM)electrolyzer have attracted increasing attention from the industrial and researchers in recent years due to its excellent hydrogen production performance.Developing accurate models to pred...Proton exchange membrane(PEM)electrolyzer have attracted increasing attention from the industrial and researchers in recent years due to its excellent hydrogen production performance.Developing accurate models to predict their performance is crucial for promoting and accelerating the design and optimization of electrolysis systems.This work developed a Koopman model predictive control(MPC)method incorporating fuzzy compensation for regulating the anode and cathode pressures in a PEM electrolyzer.A PEM electrolyzer is then built to study pressure control and provide experimental data for the identification of the Koopman linear predictor.The identified linear predictors are used to design the Koopman MPC.In addition,the developed fuzzy compensator can effectively solve the Koopman MPC model mismatch problem.The effectiveness of the proposed method is verified through the hydrogen production process in PEM simulation.展开更多
Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize...Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co_(4)N@Fe/N-C for rechargeable zinc-air batteries and overall water-splitting electrolyzers.As confirmed by theoretical and experimental results,the high intrinsic oxygen reduction reaction,oxygen evolution reaction,and hydrogen evolution reaction activities of Co_(4)N@Fe/N-C were attributed to the formation of the heterointerface and the modulated local electronic structure.Moreover,Co_(4)N@Fe/N-C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure,uniform distribution of Co_(4)N,and conductive encapsulation by Fe/N-C.Thus,the rechargeable zinc-air battery with Co_(4)N@Fe/N-C delivers a high specific capacity of 789.9 mAh g^(-1) and stable voltage profiles over 500 cycles.Furthermore,the overall water electrolyzer with Co_(4)N@Fe/N-C achieved better durability and rate performance than that with the Pt/C and IrO2 catalysts,delivering a high Faradaic efficiency of 96.4%.Along with the great potential of the integrated water electrolyzer powered by a zinc-air battery for practical applications,therefore,the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion.展开更多
1.Introduction Hydrogen is an ideal energy carrier to tackle the energy crisis and greenhouse effect,because of its high energy density and low emission.The production,storage and transportation of hydrogen are key fa...1.Introduction Hydrogen is an ideal energy carrier to tackle the energy crisis and greenhouse effect,because of its high energy density and low emission.The production,storage and transportation of hydrogen are key factors to the practical application of hydrogen energy.As the scientific and technological understanding of the electrochemical devices was advancing in the past few decades,water electrolyzers based on the proton exchange membrane (PEM) have attracted much focus for its huge potential on the production of hydrogen via water splitting.PEM electrolyzers use perfluorinated sulfonic acid (PFSA) based membranes as the electrolyte.展开更多
基金supported by the National Key Research and Development Program of China(No.2021YFB4000603)the National Natural Science Foundation of China(Nos.52273277 and U24A2062)+2 种基金Jilin Province Science and Technology Development Plan Funding Project(No.SKL202302039)Youth Innovation Promotion Association CAS(No.2021223)funding from National Natural Science Foundation of China Outstanding Youth Science Foundation of China(Overseas).
文摘Proton-exchange membrane fuel cell and water electrolyzer(PEMFC and PEMWE)with high conversion efficiency and zero-carbon emission stand out as an attractive strategy for efficient conversion between hydrogen energy and renewable electricity.As a key component,efficient oxygen electrocatalyst for promoting sluggish reaction kinetics of oxygen reduction and evolution reaction(ORR and OER)under harsh operation conditions severely limited progress of these devices.Among various candidates,Ptgroup(Pt,Ir,and Ru)-based electrocatalysts are still the most active ORR/OER catalysts.However,the scarcity,high cost,and questionable stability restrict the widespread applications and the commercialization of PEMWE/PEMFC.Progresses in synthesizing atomically dispersed single/multiple-atom catalysts(SACs/MACs)offer new opportunities to Pt-group ORR/OER catalysts owing to nearly 100% metal utilization and high catalytic activities.Extensive efforts have been continuously devoted to optimizing the local structure of Pt-group OER/ORR catalysts at atom-level for further enhancing stability and activity.In this review,universal synthesis methods to prepare Ptgroup SACs are discussed first,highlighting crucial factors which affect the structure and catalytic performance.Afterward,advanced characterization techniques for directly confirming atomic dispersed metal atoms were introduced,including aberration-corrected high-angle-annular-dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy.Importantly,considerations for rational catalyst design and typical Pt-group SACs/MACs are summarized regarding the regulation strategy of atomically dispersed metal sites and various supports,and effects of metal-support interaction on the catalytic performance.Finally,key challenges and proposed perspectives for future development of atomically dispersed Pt-group oxygen electrocatalysts for fuel cell and electrolyzer are briefly discussed.
基金supported by the National Natural Science Foundation of China(Nos.52122308 and 22305225)the Postdoctoral Fellowship Program of CPSF(No.GZC20232391).
文摘The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis,with anion-exchange membrane water electrolyzers(AEMWEs)emerging as a cost-effective alternative by combining the merits of alkaline water electrolyzers(AWEs)and proton-exchange membrane water electrolyzers(PEMWEs).However,challenges persist in membrane stability,oxygen evolution reaction(OER)kinetics,and mass transport efficiency.This review highlights the pivotal role of transition metal-based layered double hydroxides(LDHs)as high-performance,non-precious OER catalysts for AEMWEs,emphasizing their tunable electronic structures,abundant active sites,and alkaline stability.We systematically outline LDHs synthesis strategies(top-down/bottom-up approaches,and self-supporting LDHs engineering on the conductive substrates),and AEMWE component design,including membraneelectrode assembly optimization and ionomer-free architectures.Standardized evaluation protocols-short-circuit inspection,impedance spectroscopy,and durability assessment are detailed to benchmark performance.Moreover,recent advances in LDHs modification(cation/anion doping,heterojunction design,three-dimensional(3D)electrode structuring)are discussed for alkaline-fed systems,alongside emerging applications in seawater and pure-water electrolysis.By correlating material innovations with device-level metrics,this work provides a roadmap to address scalability challenges,offering perspectives on advancing AEMWEs for sustainable,large-scale hydrogen production.
文摘Proton Exchange Membrane Water Electrolyzers(PEMWE)are efficient and sustainable hydrogen production devices.This article analyzes their static and dynamic electrical models integrated with degradation mechanisms.Static models reveal steady-state behavior,while dynamic models capture transient responses to input variations.The developed modeling approach combines the activation and diffusion phenomena,resulting in a novel PEMWE model that closely reflects real-world conditions and enables fast simulations.The electrical model is integrated with the aging model through two key ratios,surface degradation ratio and membrane degradation ratio,which characterize degradation mechanisms affecting electrode and membrane performance.The linear model using second-order Taylor approximation enables the development of a diagnosis approach that can contribute to estimating the remaining useful life of PEMWEs.By associating aging models with electrical models through the proposed ratios,a deeper understanding is achieved regarding how degra-dation phenomena evolve and influence electrolyzer efficiency and durability.The integrated framework enables predictive maintenance strategies,making it valuable for industrial hydrogen production applications.
基金financial support of the National Natural Science Foundation of China(22478450,22478451,22408408)Guangdong Basic and Applied Basic Research Foundation(2024A1515012565,2021A1515010167,2022A1515011196)+3 种基金Guangzhou Key R&D Program/Plan Unveiled Flagship Project(20220602JBGS02)Guangzhou Basic and Applied Basic Research Project(202201011449)Research Fund Program of Guangdong Provincial Key Laboratory of Fuel Cell Technology(FC202220,FC202216)100 Talent Research Foundation of Sun Yat-sen University(76110-12230029)。
文摘Designing efficient and durable hydrogen evolution reaction(HER)catalysts for seawater electrolysis is crucial for large-scale hydrogen production.Here,we introduce a theory-driven design of metal/WN electrocatalysts,with metal strongly coupled to lattice-matched WN.Theoretical calculations for Pt/WN reveal that W sites enhance H_(2)O adsorption/dissociation,optimizing Pt's H binding.The prepared Pt/WN@CP nanorods can catalyze HER with low overpotentials of 107 and 113 mV at 500 mA cm^(-2)in alkaline water/seawater,respectively,surpassing Pt/C.Extended calculations and experiments show that the optimized Ni/WN@CP-90 achieves an optimal ΔG_(H*)and overpotential of 219 mV at 500 mA cm^(-2)in alkaline seawater,demonstrating the versatility of the WN support to promote HER activity.Notably,the anion exchange membrane water electrolyzer(AEMWE)constructed by Pt/WN@CP or Ni/WN@CP-90 with NiFe-LDH@NF demonstrates outstanding hydrogen production activity with excellent Faraday efficiency(~100%)and durability(120 h),indicating the potential application of WN-supported catalysts for efficient and stable seawater electrolysis.
基金National Natural Science Foundation of China (Nos. 52488201, 52076177, and 52476222)China National Key Research and Development Plan Project (No. 2021YFF0500503)+1 种基金Key Research and Development Program of Shaanxi (No. 2024GH-YBXM-02)China Fundamental Research Funds for the Central Universities。
文摘Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen (H_(2)) and electricity.However,the design and development of such systems is still in its infancy.Herein,an integrated hydrogen-oxygen (O_(2))-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate (NaNiHCF) and Zn^(2+)/Zn as dual redox electrodes.The decoupled electrolyzer enables to produce H_(2)and O_(2)in different time and space with almost 100%Faradaic efficiency at 100 mA cm^(-2).Then,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A cm^(-2).By connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.
基金National Natural Science Foundation of China(22379083)State Key Laboratory of Chemical Engineering(SKL-ChE-23T02)+2 种基金financial support from Beijing National Laboratory for Molecular Sciencessupport from Tsinghua International School’s Research Mentoring Programsupport from Tsinglan School’s Research Mentoring Program。
文摘Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO_(2)emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO_(2)using alkaline solutions with reactive absorption.In this work,we present a CO_(2)-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm^(2)electrode area.Our electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended periods.The techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.
基金supported by the National Natural Science Foundation of China(Nos.52371222 and 52271211)the Natural Science Foundation of Hunan Province in China(Nos.2025JJ60350,2024JJ4022,and 2023JJ30277)+1 种基金the Key Research and Development Program of Hunan Province(No.2023GK2035)HORIZON–Marie Sk?odowska–Curie Actions–2021–PF(No.101065098),European Union
文摘Developing efficient and stable catalysts for the hydrogen evolution reaction(HER)is essential for advancing anion-exchange membrane water electrolyzer(AEMWE)technology.In this study,we present a facile microwave reduction and low-temperature phosphorization strategy to synthesize a highly efficient HER catalyst,comprising P,N-codoped carbon-supported RuP_(2)nanocluster(RuP_(2)@PNC).RuP_(2)@PNC demonstrates outstanding HER performance,achieving overpotentials of 18 and 44 mV at a current density of 10 mA cm^(-2)in alkaline and acidic media,respectively.Furthermore,an AEMWE device utilizing RuP_(2)@PNC as the cathode catalyst delivers a current density of 0.5 A cm^(-2)at a cell voltage of 1.84 V and exhibits remarkable stability over 150 h of operation.Experimental analyses and density functional theory(DFT)calculations reveal that the synergistic effects of P,N-codoped and the unique structure of RuP_(2)enhance electron transfer between Ru and the support,optimize the electronic structure,and regulate the d–band center of Ru.These features improve water adsorption,weaken the Ru–H binding strength,and facilitate efficient H_(2)desorption,collectively driving the superior HER activity of RuP_(2)@PNC.This work offers an effective design strategy for high-performance HER catalysts and provides valuable insights for accelerating the development of AEMWE technology.
基金supported by the National Research Foundation of Korea(RS-2023-00207831,RS-2024-00346153).
文摘The state-of-the-art anion-exchange membrane water electrolyzers(AEMWEs)require highly stable electrodes for prolonged operation.The stability of the electrode is closely linked to the effective evacuation of H_(2) or O_(2) gas generated from electrode surface during the electrolysis.In this study,we prepared a superhydrophilic electrode by depositing porous nickel–iron nanoparticles on annealed TiO_(2) nanotubes(NiFe/ATNT)for rapid outgassing of such nonpolar gases.The super-hydrophilic NiFe/ATNT electrode exhibited an overpotential of 235 mV at 10 mA cm^(−2) for oxygen evolution reaction in 1.0 M KOH solution,and was utilized as the anode in the AEMWE to achieve a current density of 1.67 A cm^(−2) at 1.80 V.In addition,the AEMWE with NiFe/ATNT electrode,which enables effective outgassing,showed record stability for 1500 h at 0.50 A cm^(−2) under harsh temperature conditions of 80±3℃.
基金supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.15308024)a grant from Research Centre for Carbon-Strategic Catalysis,The Hong Kong Polytechnic University(CE2X).
文摘Water electrolyzers play a crucial role in green hydrogen production.However,their efficiency and scalability are often compromised by bubble dynamics across various scales,from nanoscale to macroscale components.This review explores multi-scale modeling as a tool to visualize multi-phase flow and improve mass transport in water electrolyzers.At the nanoscale,molecular dynamics(MD)simulations reveal how electrode surface features and wettability influence nanobubble nucleation and stability.Moving to the mesoscale,models such as volume of fluid(VOF)and lattice Boltzmann method(LBM)shed light on bubble transport in porous transport layers(PTLs).These insights inform innovative designs,including gradient porosity and hydrophilic-hydrophobic patterning,aimed at minimizing gas saturation.At the macroscale,VOF simulations elucidate two-phase flow regimes within channels,showing how flow field geometry and wettability affect bubble discharging.Moreover,artificial intelligence(AI)-driven surrogate models expedite the optimization process,allowing for rapid exploration of structural parameters in channel-rib flow fields and porous flow field designs.By integrating these approaches,we can bridge theoretical insights with experimental validation,ultimately enhancing water electrolyzer performance,reducing costs,and advancing affordable,high-efficiency hydrogen production.
基金financially supported by the Natural Science Foundation of Hunan Province(2023JJ40608,2024JJ6413)the Majoy Project of the Education Department of Hunan Province(24A0610).
文摘Proton exchange membrane water electrolysis(PEMWE)technology is widely recognized as a cornerstone for green hydrogen production,offering high operational current densities exceeding 1.0 A cm^(-2),rapid dynamic response capabilities,and zero-carbon emission characteristics[1].However,the sluggish kinetics of oxygen evolution reaction(OER)at the anode presents a critical bottleneck for large-scale commercial deployment(Fig.1(a)).Despite significant advancements through electronic structure modulation[2]and coordination environment optimization[3],the deprotonation energy barrier of oxygen-containing intermediates and the stability of active sites under acidic conditions remain unresolved challenges.
基金supported by the National Natural Science Foundation of China (Nos. 22171287, 51972342, 52303274)Taishan Scholar Project of Shandong Province (tsqn202103046 and ts20190922)+1 种基金Natural Science Foundation of Shandong Province (ZR2024QB076, ZR2022QE175)Fundamental Research Funds for the Central Universities (24CX07007A and 22CX01002A-1)
文摘Creating strongly coupled heterostructures with favorable catalytic activities is crucial for promoting the performance of catalytic reactions,especially those involve multiple intermediates.Herein,we fabricated a strongly coupled platinum/molybdenum nitrides nanocluster heterostructure on nitrogen-doped reduced graphene oxide(Pt/Mo_(2)N-NrGO)for alkaline hydrogen evolution reaction.The well-defined Pt-containing Anderson-type polyoxometalates promote strong interfacial Pt-N-Mo bonding in Pt/Mo_(2)N-NrGO,which exhibits a remarkably low overpotential,high mass activity,and exceptional long-term durability(>500 h at 1500 mA cm^(-2))in an anion-exchange membrane water electrolyzer(AEMWE).Operando Raman spectroscopy and density functional theory reveal that pronounced electronic coupling at the Pt/Mo_(2)N cluster interface facilitates the catalytic decomposition of H_(2)O through synergistic stabilization of intermediates(Pt-H^(*)and Mo-OH^(*)),thereby enhancing the kinetics of the rate-determining Volmer step.Techno-economic analysis indicates a levelized hydrogen production cost of$2.02 kg^(-1),meeting the US DOE targets.Our strategy presents a viable pathway to designing next-generation catalysts for industrial AEMWE for green hydrogen production.
基金King Abdullah University of Science and Technology for funding through the funding grant (BAS/1/1413-01-01)the Engineering and Physical Sciences Research Council (EPSRC,EP/V027433/1)+1 种基金the Royal Society (RGSR1211080IESR2212115)。
文摘Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surface is covered with water, there is inadequacy of freshwater in most parts of the world. Hence, splitting seawater instead of freshwater could be a truly sustainable alternative. However, direct seawater splitting faces challenges because of the complex composition of seawater. The composition, and hence, the local chemistry of seawater may vary depending on its origin, and in most cases, tracking of the side reactions and standardizing and customizing the catalytic process will be an extra challenge. The corrosion of catalysts and competitive side reactions due to the presence of various inorganic and organic pollutants create challenges for developing stable electro-catalysts. Hence, seawater splitting generally involves a two-step process, i.e., purification of seawater using reverse osmosis and then subsequent fresh water splitting. However, this demands two separate chambers and larger space, and increases complexity of the reactor design. Recently, there have been efforts to directly split seawater without the reverse osmosis step. Herein, we represent the most recent innovative approaches to avoid the two-step process, and compare the potential application of membrane-assisted and membrane-less electrolyzers in direct seawater splitting(DSS). We particularly discuss the device engineering, and propose a novel electrolyzer design strategies for concentration gradient based membrane-less microfluidic electrolyzer.
基金supported by National Key R&D Program of China(2020YFA0710200)the National Natural Science Foundation of China(21838010,22122814)+2 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2018064)State Key Laboratory of Multiphase complex systems,Institute of Process Engineering,Chinese Academy of Sciences(No.MPCS-2022-A-03)Innovation Academy for Green Manufacture Institute,Chinese Academy of Science(IAGM2020C14).
文摘CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at design and understanding of catalytic materials and electrolyte systems,the CO_(2) ER performance(such as current density,selectivity,stability,CO_(2) conversion,etc.)has been continually increased.Unfortunately,there has been relatively little attention paid to the large-scale CO 2 electrolyzers,which stand just as one obstacle,alongside series-parallel integration,challenging the practical application of this infant technology.In this review,the latest progress on the structures of low-temperature CO_(2) electrolyzers and scale-up studies was systematically overviewed.The influence of the CO_(2) electrolyzer configurations,such as the flow channel design,gas diffusion electrode(GDE)and ion exchange membrane(IEM),on the CO_(2) ER performance was further discussed.The review could provide inspiration for the design of large-scale CO_(2) electrolyzers so as to accelerate the industrial application of CO_(2) ER technology.
基金financially supported by the National Natural Science Foundation of China(U1664259)State Grid Corporation of China(No.SGTYHT/15-JS-191,PEMWE MEA Preparation and degradation mechanism)
文摘An effective oxygen evolution electrode with Ir0.6Sn0.4O2 was designed for proton exchange membrane(PEM)water electrolyzers.The anode catalyst layer exhibits a jagged structure with smaller particles and pores,which provide more active sites and mass transportation channels.The prepared IrSn electrode showed a cell voltage of 1.96 V at 2.0 A cm^-2 with Ir loading as low as 0.294 mg cm^-2.Furthermore,Ir Sn electrode with different anode catalyst loadings was investigated.The IrS n electrode indicates higher mass current and more stable cell voltage than the commercial Ir Black electrode at low loading.
基金National Natural Science Foundation of China(Nos.52071231,51722103)the Natural Science Foundation of Tianjin(No.19JCJQJC61900)。
文摘Anion exchange membrane(AEM)electrolysis is a promising membrane-based green hydrogen production technology.However,AEM electrolysis still remains in its infancy,and the performance of AEM electrolyzers is far behind that of well-developed alkaline and proton exchange membrane electrolyzers.Therefore,breaking through the technical barriers of AEM electrolyzers is critical.On the basis of the analysis of the electrochemical performance tested in a single cell,electrochemical impedance spectroscopy,and the number of active sites,we evaluated the main technical factors that affect AEM electrolyzers.These factors included catalyst layer manufacturing(e.g.,catalyst,carbon black,and anionic ionomer)loadings,membrane electrode assembly,and testing conditions(e.g.,the KOH concentration in the electrolyte,electrolyte feeding mode,and operating temperature).The underlying mechanisms of the effects of these factors on AEM electrolyzer performance were also revealed.The irreversible voltage loss in the AEM electrolyzer was concluded to be mainly associated with the kinetics of the electrode reaction and the transport of electrons,ions,and gas-phase products involved in electrolysis.Based on the study results,the performance and stability of AEM electrolyzers were significantly improved.
基金the National Natural Science Foundation of China(No.52125102)the National Key Research and Development Program of China(No.2021YFB4000101)Fundamental Research Funds for t he Central Universities(No.FRF-TP-2021-02C2)。
文摘Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen energy.Proton-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and compactness.Bipolar plates account for a relatively high percentage of the total cost and weight compared with other components of PEMWEs.Thus,optimization of their design may accelerate the promotion of PEMWEs.This paper reviews the advances in materials and flow-field design for bipolar plates.First,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and potential.Then,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are presented.Furthermore,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are explored.Finally,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science.
基金financially supported by the National Natural Science Foundation of China(No.52074130)the Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality,Ministry of Education。
文摘Alkaline water electrolysis(AWE)is the most mature technology for hydrogen production by water electrolysis.Alkaline water electrolyzer consists of multiple electrolysis cells,and a single cell consists of a diaphragm,electrodes,bipolar plates and end plates,etc.The existing industrial bipolar plate channel is concave-convex structure,which is manufactured by complicated and high-cost mold punching.This structure still results in uneven electrolyte flow and low current density in the electrolytic cell,further increasing in energy consumption and cost of AWE.Thereby,in this article,the electrochemical and flow model is firstly constructed,based on the existing industrial concave and convex flow channel structure of bipolar plate,to study the current density,electrolyte flow and bubble distribution in the electrolysis cell.The reliability of the model was verified by comparison with experimental data in literature.Among which,the electrochemical current density affects the bubble yield,on the other hand,the generated bubbles cover the electrode surface,affecting the active specific surface area and ohmic resistance,which in turn affects the electrochemical reaction.The result indicates that the flow velocity near the bottom of the concave ball approaches zero,while the flow velocity on the convex ball surface is significantly higher.Additionally,vortices are observed within the flow channel structure,leading to an uneven distribution of electrolyte.Next,modelling is used to optimize the bipolar plate structure of AWE by simulating the electrochemistry and fluid flow performances of four kinds of structures,namely,concave and convex,rhombus,wedge and expanded mesh,in the bipolar plate of alkaline water electrolyzer.The results show that the expanded mesh channel structure has the largest current density of 3330 A/m^(2)and electrolyte flow velocity of 0.507 m/s in the electrolytic cell.Under the same current density,the electrolytic cell with the expanded mesh runner structure has the smallest potential and energy consumption.This work provides a useful guide for the comprehensive understanding and optimization of channel structures,and a theoretical basis for the design of large-scale electrolyzer.
基金supported by 2022 Zhejiang Provincial Science and Technology Plan Project(2022C01035).
文摘Proton exchange membrane(PEM)electrolyzer have attracted increasing attention from the industrial and researchers in recent years due to its excellent hydrogen production performance.Developing accurate models to predict their performance is crucial for promoting and accelerating the design and optimization of electrolysis systems.This work developed a Koopman model predictive control(MPC)method incorporating fuzzy compensation for regulating the anode and cathode pressures in a PEM electrolyzer.A PEM electrolyzer is then built to study pressure control and provide experimental data for the identification of the Koopman linear predictor.The identified linear predictors are used to design the Koopman MPC.In addition,the developed fuzzy compensator can effectively solve the Koopman MPC model mismatch problem.The effectiveness of the proposed method is verified through the hydrogen production process in PEM simulation.
基金National Research Foundation of Korea,Grant/Award Numbers:NRF-2020R1A3B2079803,2021R1A2C2007804。
文摘Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co_(4)N@Fe/N-C for rechargeable zinc-air batteries and overall water-splitting electrolyzers.As confirmed by theoretical and experimental results,the high intrinsic oxygen reduction reaction,oxygen evolution reaction,and hydrogen evolution reaction activities of Co_(4)N@Fe/N-C were attributed to the formation of the heterointerface and the modulated local electronic structure.Moreover,Co_(4)N@Fe/N-C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure,uniform distribution of Co_(4)N,and conductive encapsulation by Fe/N-C.Thus,the rechargeable zinc-air battery with Co_(4)N@Fe/N-C delivers a high specific capacity of 789.9 mAh g^(-1) and stable voltage profiles over 500 cycles.Furthermore,the overall water electrolyzer with Co_(4)N@Fe/N-C achieved better durability and rate performance than that with the Pt/C and IrO2 catalysts,delivering a high Faradaic efficiency of 96.4%.Along with the great potential of the integrated water electrolyzer powered by a zinc-air battery for practical applications,therefore,the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion.
基金supported by the National Key R&D Program of China(2021YFA1500900,2020YFA0710000)the National Natural Science Foundation of China(22172047,22002039,21825201 and U19A2017)+3 种基金the Provincial Natural Science Foundation of Hunan(2021JJ30089,2016TP1009 and 2020JJ5045)the China Postdoctoral Science Foundation(2019M662759,2020M682541 and 2020M682549)the Shenzhen Science and Technology Program(JCYJ20210324122209025)the Changsha Municipal Natural Science Foundation(kq2107008 and kq2007009)。
文摘1.Introduction Hydrogen is an ideal energy carrier to tackle the energy crisis and greenhouse effect,because of its high energy density and low emission.The production,storage and transportation of hydrogen are key factors to the practical application of hydrogen energy.As the scientific and technological understanding of the electrochemical devices was advancing in the past few decades,water electrolyzers based on the proton exchange membrane (PEM) have attracted much focus for its huge potential on the production of hydrogen via water splitting.PEM electrolyzers use perfluorinated sulfonic acid (PFSA) based membranes as the electrolyte.
