Proton exchange membrane water electrolysis(PEMWE)is a favorable technology for producing highpurity hydrogen under high current density using intermittent renewable energy.The performance of PEMWE is largely determin...Proton exchange membrane water electrolysis(PEMWE)is a favorable technology for producing highpurity hydrogen under high current density using intermittent renewable energy.The performance of PEMWE is largely determined by the oxygen evolution reaction(OER),a sluggish four-electron reaction with a high reaction barrier.Nowadays,iridium(Ir)-based catalysts are the catalysts of choice for OER due to their excellent activity and durability in acidic solution.However,its high price and unsatisfactory electrochemical performance severely restrict the PEMWE’s practical application.In this review,we initiate by introducing the current OER reaction mechanisms,namely adsorbate evolution mechanism and lattice oxygen mechanism,with degradation mechanisms discussed.Optimized strategies in the preparation of advanced Ir-based catalysts are further introduced,with merits and potential problems also discussed.The parameters that determine the performance of PEMWE are then introduced,with unsolved issues and related outlooks summarized in the end.展开更多
Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity...Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity hydrogen for aerospace and high-end manufacturing applications. Withthe ongoing commercialization of PEMWE, advancing iridium-based oxygen evolution reaction(OER) catalysts remains imperative to reconcile stringent requirements for high activity, extendedlongevity, and minimized noble metal loading. The review provides a systematic analysis of theintegrated design of iridium-based catalysts in PEMWE, starting from the fundamentals of OER,including the operation environment of OER catalysts, catalytic performance evaluation withinPEMWE, as well as catalytic and dissolution mechanisms. Subsequently, the catalyst classificationand preparation/characterization techniques are summarized with the focus on the dynamic structure-property relationship. Guided by these understandings, an overview of the design strategiesfor performance enhancement is presented. Specifically, we construct a mathematical frameworkfor cost-performance optimization to offer quantitative guidance for catalyst design. Finally, futureperspectives are proposed, aiming to establish a theoretical framework for rational catalyst design.展开更多
Iridium(Ir)-based superalloys withγ/γ'twophase microstructure are recognized as next-generation high-temperature materials for aerospace engines operating above 1500℃.The strengthening phases can markedly enhan...Iridium(Ir)-based superalloys withγ/γ'twophase microstructure are recognized as next-generation high-temperature materials for aerospace engines operating above 1500℃.The strengthening phases can markedly enhance the mechanical strength of alloys.However,these phases exhibit significant brittleness,and their properties in Ir-based alloys remain insufficiently investigated.Here,the high-throughput calculations were employed to screen the potentialγ'phases for Ir_(3)X(X=Al,Si,Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Y,Zr,Nb,Mo,Tc,Ru,Rh,Pd,Ag,Cd,La,Hf,Ta,W,Re,Os,Pt,Au,Th)through systematic assessment of phase stability,melting points,shear modulus and anti-phase boundary(APB)energies.Subsequently,lattice misfit was further optimized through thirdelement compositional design in Ir_(3)(Ti_(0.5)X_(0.5))(X=Nb,Hf,Zr,Ta).The dependence of yield strength on precipitate size was systematically evaluated through the precipitation strengthening effect.Ir_(3)(Ti_(0.5)Ta_(0.5))displays a reduced lattice misfit(0.63%),accompanied by a higher shear modulus(207 GPa),elevated APB energy(920 mJ m^(-2)),and an increased Poisson's ratio(0.25),demonstrating a synergistic improvement in these interrelated mechanical characteristics.The increase of density of states value at Fermi level and the right-shift of the peak in the bonding region result in the improved ductility.The greatest delocalization degree of electrons around Ta and the shorter Ir-Ta bond lengths are responsible for its higher shear modulus and APB energies.A novel Ir_(3)(Ti_(0.5)Ta_(0.5))composition balancing the trade-off between high strength and ductility is expected to guide the development of Irbased superalloys.展开更多
Proton exchange membrane water electrolysis(PEMWE)has emerged as a promising technology for hydrogen production,offering high efficiency,superior hydrogen purity,and a compact system design.However,its widespread adop...Proton exchange membrane water electrolysis(PEMWE)has emerged as a promising technology for hydrogen production,offering high efficiency,superior hydrogen purity,and a compact system design.However,its widespread adoption is hindered by the harsh acidic environment and the intrinsically slow kinetics of the oxygen evolution reaction(OER)at the anode.Addressing these challenges requires the development of robust,acidresistant anode catalysts.Among various candidates,iridium-based catalysts(IBCs)have attracted significant attention owing to their exceptional catalytic activity and stability under acidic conditions.Nevertheless,the high cost and limited availability of Ir impede their large-scale application.To mitigate these issues,extensive research has been devoted to strategies that reduce Ir loading while enhancing catalytic performance.This review provides a comprehensive and systematic overview of recent advances in the rational design of IBCs,focusing on strategies such as multi-scale morphology control,heteroatom doping,alloying,defect engineering,heterostructure construction,and support interactions.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFB4004100)National Natural Science Foundation of China(Nos.U22A20396,22209168)+1 种基金Natural Science Foundation of Anhui Province(No.2208085UD04)Liaoning Binhai Laboratory(No.LBLF-2023-04),and Shandong Energy Institute(No.SEI U202307).
文摘Proton exchange membrane water electrolysis(PEMWE)is a favorable technology for producing highpurity hydrogen under high current density using intermittent renewable energy.The performance of PEMWE is largely determined by the oxygen evolution reaction(OER),a sluggish four-electron reaction with a high reaction barrier.Nowadays,iridium(Ir)-based catalysts are the catalysts of choice for OER due to their excellent activity and durability in acidic solution.However,its high price and unsatisfactory electrochemical performance severely restrict the PEMWE’s practical application.In this review,we initiate by introducing the current OER reaction mechanisms,namely adsorbate evolution mechanism and lattice oxygen mechanism,with degradation mechanisms discussed.Optimized strategies in the preparation of advanced Ir-based catalysts are further introduced,with merits and potential problems also discussed.The parameters that determine the performance of PEMWE are then introduced,with unsolved issues and related outlooks summarized in the end.
文摘Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity hydrogen for aerospace and high-end manufacturing applications. Withthe ongoing commercialization of PEMWE, advancing iridium-based oxygen evolution reaction(OER) catalysts remains imperative to reconcile stringent requirements for high activity, extendedlongevity, and minimized noble metal loading. The review provides a systematic analysis of theintegrated design of iridium-based catalysts in PEMWE, starting from the fundamentals of OER,including the operation environment of OER catalysts, catalytic performance evaluation withinPEMWE, as well as catalytic and dissolution mechanisms. Subsequently, the catalyst classificationand preparation/characterization techniques are summarized with the focus on the dynamic structure-property relationship. Guided by these understandings, an overview of the design strategiesfor performance enhancement is presented. Specifically, we construct a mathematical frameworkfor cost-performance optimization to offer quantitative guidance for catalyst design. Finally, futureperspectives are proposed, aiming to establish a theoretical framework for rational catalyst design.
基金financially supported by the Major R&D Project of Yunnan Province(Nos.202302AB080021 and 202402AB080007)the Major R&D Project of Yunnan Precious Metals Laboratory Co.,Ltd.(No.YPML-2023050205)+1 种基金Yunnan Major Research and Development Plan(No.202403AA080016)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd.(No.YPML-20240502066)
文摘Iridium(Ir)-based superalloys withγ/γ'twophase microstructure are recognized as next-generation high-temperature materials for aerospace engines operating above 1500℃.The strengthening phases can markedly enhance the mechanical strength of alloys.However,these phases exhibit significant brittleness,and their properties in Ir-based alloys remain insufficiently investigated.Here,the high-throughput calculations were employed to screen the potentialγ'phases for Ir_(3)X(X=Al,Si,Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Y,Zr,Nb,Mo,Tc,Ru,Rh,Pd,Ag,Cd,La,Hf,Ta,W,Re,Os,Pt,Au,Th)through systematic assessment of phase stability,melting points,shear modulus and anti-phase boundary(APB)energies.Subsequently,lattice misfit was further optimized through thirdelement compositional design in Ir_(3)(Ti_(0.5)X_(0.5))(X=Nb,Hf,Zr,Ta).The dependence of yield strength on precipitate size was systematically evaluated through the precipitation strengthening effect.Ir_(3)(Ti_(0.5)Ta_(0.5))displays a reduced lattice misfit(0.63%),accompanied by a higher shear modulus(207 GPa),elevated APB energy(920 mJ m^(-2)),and an increased Poisson's ratio(0.25),demonstrating a synergistic improvement in these interrelated mechanical characteristics.The increase of density of states value at Fermi level and the right-shift of the peak in the bonding region result in the improved ductility.The greatest delocalization degree of electrons around Ta and the shorter Ir-Ta bond lengths are responsible for its higher shear modulus and APB energies.A novel Ir_(3)(Ti_(0.5)Ta_(0.5))composition balancing the trade-off between high strength and ductility is expected to guide the development of Irbased superalloys.
基金financially supported by the National Natural Science Foundation of China(Nos.22209115,52472226,and U23A20573)the Key Research and Development Program of Shandong Province(No.2022CXGC010305)+2 种基金Guangdong Basic and Applied Basic Research Foundation(Nos.2023B1515120022,2022B1515120001 and 2025A1515011809)Shenzhen Science and Technology Innovation Program(Nos.RCBS20231211090522040,KJZD20240903095610014 and KJZD20240903095712017)the High-Level Professional Team in Shenzhen(No.KQTD20210811090045006)
文摘Proton exchange membrane water electrolysis(PEMWE)has emerged as a promising technology for hydrogen production,offering high efficiency,superior hydrogen purity,and a compact system design.However,its widespread adoption is hindered by the harsh acidic environment and the intrinsically slow kinetics of the oxygen evolution reaction(OER)at the anode.Addressing these challenges requires the development of robust,acidresistant anode catalysts.Among various candidates,iridium-based catalysts(IBCs)have attracted significant attention owing to their exceptional catalytic activity and stability under acidic conditions.Nevertheless,the high cost and limited availability of Ir impede their large-scale application.To mitigate these issues,extensive research has been devoted to strategies that reduce Ir loading while enhancing catalytic performance.This review provides a comprehensive and systematic overview of recent advances in the rational design of IBCs,focusing on strategies such as multi-scale morphology control,heteroatom doping,alloying,defect engineering,heterostructure construction,and support interactions.
