Self-supported,hot-pressed FeNiCoCuMo high-entropy alloy(HEA)electrodes were fabricated and characterized by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HR-TEM),and energy dispersive spectr...Self-supported,hot-pressed FeNiCoCuMo high-entropy alloy(HEA)electrodes were fabricated and characterized by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HR-TEM),and energy dispersive spectroscopy(EDS),confirming a face-centered cubic(FCC)matrix with minor body-centered cubic(BCC)phase(~1wt%).We map the redox behavior of the individual constituents(Fe,Ni,Co,Cu,and Mo)and compare it with HEA to reveal solid-solution synergy(“cocktail effect”).Electrochemistry(cyclic voltammetry(CV)/linear sweep voltammetry(LSV)/Tafel in 1.0 M KOH)and X-ray photoelectron spectroscopy(XPS)show broadened redox features for HEA and Ni/Co-rich(oxy)hydroxide signatures with MoOx contributions.Triplicate electrodes(M1–M3)deliver an average overpotential of 370 m V at 10mA·cm^(-2)and a Tafel slope of 78 mV·dec^(-1),outperforming monometallic references and remaining competitive with the literature-reported RuO_(2).Chronopotentiometry 100 h evidence stable operation;post-mortem XRD indicates a thin reconstructed surface while the bulk remains FCC-dominated.Density functional theory(DFT)supports broadened electronic states near the Fermi level and enhanced charge transfer.Overall,structure and computation link compositional disorder,surface reconstruction,and oxygen evolution reaction(OER)kinetics in a robust anode for alkaline oxygen evolution.展开更多
基金financial support from Universidad de Santiago de Chile through the Dirección de Investigación Científica y Tecnológica(DICYT,Project No.022442PC)the Vicerrectoría de Investigación,Innovación y Creación,Fondo de Equipamiento Científico y Tecnológico(FONDEQUIP,EQM180195)+6 种基金FONDECYT Postdoctoral project(No.3260881)support from the Agencia Nacional de Investigación y Desarrollo(ANID,Chile)through the FONDECYT Postdoctoral Project No.3250677the Subvención a la Instalación en la Academia(SIA No.85250233)support from RPM's laboratory at Universidad Técnica Federico Santa María(UTFSM)support from the UK Engineering and Physical Sciences Research Council through the Li ME project(EP/N007638/1)support from ANID through the FONDECYT Iniciación Project No.11230550the Fondo de Financiamiento de Centros de Investigación enÁreas Prioritarias(FONDAP,No.1523A0006,Solar Energy Research Center—SERC-Chile,second extension).
文摘Self-supported,hot-pressed FeNiCoCuMo high-entropy alloy(HEA)electrodes were fabricated and characterized by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HR-TEM),and energy dispersive spectroscopy(EDS),confirming a face-centered cubic(FCC)matrix with minor body-centered cubic(BCC)phase(~1wt%).We map the redox behavior of the individual constituents(Fe,Ni,Co,Cu,and Mo)and compare it with HEA to reveal solid-solution synergy(“cocktail effect”).Electrochemistry(cyclic voltammetry(CV)/linear sweep voltammetry(LSV)/Tafel in 1.0 M KOH)and X-ray photoelectron spectroscopy(XPS)show broadened redox features for HEA and Ni/Co-rich(oxy)hydroxide signatures with MoOx contributions.Triplicate electrodes(M1–M3)deliver an average overpotential of 370 m V at 10mA·cm^(-2)and a Tafel slope of 78 mV·dec^(-1),outperforming monometallic references and remaining competitive with the literature-reported RuO_(2).Chronopotentiometry 100 h evidence stable operation;post-mortem XRD indicates a thin reconstructed surface while the bulk remains FCC-dominated.Density functional theory(DFT)supports broadened electronic states near the Fermi level and enhanced charge transfer.Overall,structure and computation link compositional disorder,surface reconstruction,and oxygen evolution reaction(OER)kinetics in a robust anode for alkaline oxygen evolution.
