摘要
以泡沫镍(NF)为基板,分别通过恒电位法(i-t)和计时电位法(CP)沉积镍铁钼铜四元合金,经去合金化处理,获得了具有高催化活性的析氢阴极电极材料NiFeMoCu/NF。电沉积过程设计了6种电解液配方进行优选,去合金化处理时采用恒电位法(i-t)分别进行了金属铜的原位溶出和独立溶出。结果表明:参照配方4的物料配比组织电解液,以计时电位法沉积四元合金,经铜的独立溶出后制得了由纳米颗粒堆积而成团簇状结构的析氢电极材料。在1mol/L KOH溶液中,催化电流密度为10mA/cm~2时,NiFeMoCu/NF电极的析氢过电位仅为65mV,其高催化活性主要归因于镍铁钼铜四元合金的金属间协同作用。
Ni-Fe-Mo-Cu quaternary alloy catalysts for hydrogen evolution reaction(HER),which was grown insitu on nickel foam(NF)substrate by potentiostatic method and chronopotentiometry,respectively,followed by electrochemical dealloying.Six formulas for optimization of electrolyte composition were designed.The in-situ and independent potentiostatic dissolution of Cu in Ni-Fe-Mo-Cu quaternary alloy were respectively achieved during the dealloying process.Results showed that the optimal electrolyte composition was formula 4,NiFeMoCu/NF with cluster structure piled by nanoparticles,prepared by chronopotentiometry followed by the independent selective dissolution of Cu from the deposits.The as-obtained cathode required an overpotential of merely 65 mV to driver a current density of10 mA·cm~(-2) for HER in 1 mol/L KOH.The excellent electrocatalytic activity can be ascribed to the intermetallic synergistic effect between the four metals.
引文
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