Efficient and stable bifunctional electrocatalysts for water splitting is essential for producing hydrogen and alleviating huge energy consumption.Meanwhile,charge transfer engineering is an efficient approach to modu...Efficient and stable bifunctional electrocatalysts for water splitting is essential for producing hydrogen and alleviating huge energy consumption.Meanwhile,charge transfer engineering is an efficient approach to modulate the localized electronic properties of catalysts and tune the electrocatalytic performance.Herein,we tactfully fabricate PtFeNi alloys/NiFe layered double hydroxides(LDHs)heterostructure by an easily electrochemical way with a small amount of Pt.The experimental and theoretical results unravel that the charge transfer on the alloy clusters modulated by the defective substrates(NiFe LDHs),which synergistically optimizes the adsorption energy of the reaction intermediates.The electrocatalyst exhibits an ultra‐low overpotential of 81 and 243 mV at the current density of 100 mA cm^(–2) for hydrogen evolution and oxygen evolution,respectively.Furthermore,the overall water splitting indicates that PtFeNi alloys/NiFe LDHs presents an ultra‐low overpotential of 265 and 406 mV to reach the current density of 10 and 300 mA cm^(–2),respectively.It proves that the PtFeNi alloys/NiFe LDHs catalyst is an excellent dual‐function electrocatalyst for water splitting and promising for industrialization.This work provides a new electrochemical approach to construct the alloy heterostructure.The prepared heterostructures act as an ideal platform to investigate the charge re‐distribution behavior and to improve the electrocatalytic activity.展开更多
High-temperature proton exchange membrane fuel cells(HT-PEMFCs)bring new opportunities for portable power generation due to their outstanding advantages such as high tolerance to fuel/air impurities and simplified hea...High-temperature proton exchange membrane fuel cells(HT-PEMFCs)bring new opportunities for portable power generation due to their outstanding advantages such as high tolerance to fuel/air impurities and simplified heat/water management.However,carbon-supported nanostructured Pt-based catalysts running at temperatures over 150℃are challenged by the severe aggregation and carbon corrosion,thus leading to poor durability.Herein,we demonstrate that dendritic Pt-Ni nanoparticles supported on fluorinated carbon black(white carbon black)could significantly enhance the performance and durability of HT-PEMFCs as the cathode catalysts running at 160℃due to the strong interaction of the F and Ni atoms to form a Ni_(x)F_(y) interface on Pt-Ni nanoparticles.With the formation of a stable Ni_(x)F_(y) interface,this integrated HT-PEMFC reached peak power densities of 906 mW cm^(−2) and demonstrated excellent durability at 160℃ under anhydrous H_(2)/O_(2) conditions.This mitigation strategy was applied to Pt-alloy/C electrocatalysts and resulted in the elimination of Pt dissolution in practical fuel cells.展开更多
基金financially supported by the National Key R&D Program of China (2021YFA1500900)the National Natural Science Foundation of China (22102053, 21825201 and U19A2017)+5 种基金the Provincial Natural Science Foundation of Hunan (2016TP1009, 2020JJ5045 and 2022JJ10006)the Science and Technology Innovation Program of Hunan Province (2022RC1036)the Major Program of the Natural Science Foundation of Hunan Province (2021JC0006)Hunan Graduate Education Innovation Project and Professional Ability Improvement Project (CX20210400)the Basic and Applied Basic Research Foundation of Guangdong Province-Regional joint fund project (2021B1515120024)Shenzhen Science and Technology Programs (JCYJ20200109110416441)。
文摘Efficient and stable bifunctional electrocatalysts for water splitting is essential for producing hydrogen and alleviating huge energy consumption.Meanwhile,charge transfer engineering is an efficient approach to modulate the localized electronic properties of catalysts and tune the electrocatalytic performance.Herein,we tactfully fabricate PtFeNi alloys/NiFe layered double hydroxides(LDHs)heterostructure by an easily electrochemical way with a small amount of Pt.The experimental and theoretical results unravel that the charge transfer on the alloy clusters modulated by the defective substrates(NiFe LDHs),which synergistically optimizes the adsorption energy of the reaction intermediates.The electrocatalyst exhibits an ultra‐low overpotential of 81 and 243 mV at the current density of 100 mA cm^(–2) for hydrogen evolution and oxygen evolution,respectively.Furthermore,the overall water splitting indicates that PtFeNi alloys/NiFe LDHs presents an ultra‐low overpotential of 265 and 406 mV to reach the current density of 10 and 300 mA cm^(–2),respectively.It proves that the PtFeNi alloys/NiFe LDHs catalyst is an excellent dual‐function electrocatalyst for water splitting and promising for industrialization.This work provides a new electrochemical approach to construct the alloy heterostructure.The prepared heterostructures act as an ideal platform to investigate the charge re‐distribution behavior and to improve the electrocatalytic activity.
基金supported by the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(21825201,U19A2017)+3 种基金the Provincial Natural Science Foundation of Hunan(2019GK2031,2016TP1009,2020JJ5045)China Postdoctoral Science Foundation(2020M682541)the Science and Technology Innovation Program of Hunan Province,China(2020RC2020)Changsha Municipal Natural Science Foundation(kq2007009)。
文摘High-temperature proton exchange membrane fuel cells(HT-PEMFCs)bring new opportunities for portable power generation due to their outstanding advantages such as high tolerance to fuel/air impurities and simplified heat/water management.However,carbon-supported nanostructured Pt-based catalysts running at temperatures over 150℃are challenged by the severe aggregation and carbon corrosion,thus leading to poor durability.Herein,we demonstrate that dendritic Pt-Ni nanoparticles supported on fluorinated carbon black(white carbon black)could significantly enhance the performance and durability of HT-PEMFCs as the cathode catalysts running at 160℃due to the strong interaction of the F and Ni atoms to form a Ni_(x)F_(y) interface on Pt-Ni nanoparticles.With the formation of a stable Ni_(x)F_(y) interface,this integrated HT-PEMFC reached peak power densities of 906 mW cm^(−2) and demonstrated excellent durability at 160℃ under anhydrous H_(2)/O_(2) conditions.This mitigation strategy was applied to Pt-alloy/C electrocatalysts and resulted in the elimination of Pt dissolution in practical fuel cells.
