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目的 降低电极的析氢过电位,提高析氢性能,从而降低电解水制氢的成本,促进氢储能技术的发展.方法 通过异相共沉积法,制备了镍钴合金电极.利用场发射扫描电镜(SEM)、电化学交流阻抗(EIS)对纯镍电极及镍钴合金电极进行表征,采用阴极极化曲线(LSV)探究了电沉积液中Ni/Co元素的比例、电沉积电位及电沉积时间对镍钴合金电极析氢性能的影响.结果 SEM结果揭示了纯镍电极及镍钴合金电极表面分别是粒径约为100 nm左右的镍颗粒和镍钴颗粒.EIS结果说明了镍钴合金电极的导电性能优于纯镍电极.此外,纯镍电极、镍钴合金电极的阴极极化曲线测试表明在电流密度为30 mA/cm2时,镍钴合金电极的析氢过电位比纯镍电极降低55 mV,降低了近20%.结论通过异相共沉积法制备镍钴合金电极,制备方法简单、方便、快速,其析氢性能优于纯镍电极.镍钴合金电极的最优制备工艺条件为:NiSO4·6H2O 27 g/L,CoSO4·7H2O 3 g/L,H3BO310 g/L,Na2SO410 g/L,柠檬酸10 g/L,十二烷基硫酸钠0.1 g/L,pH值4.0,电沉积电位?1.3 V,电沉积时间10 s.

The work aims to reduce cost of hydrogen production from electrolyzed water and facilitate the development of hydrogen economy by reducing hydrogen overpotential of electrodes and improving hydrogen evolution property. Ni-Co alloy electrodes were prepared in heterogeneous co-deposition method. Ni electrodes and Ni-Co alloy electrodes were characterized with scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS). Effects of ratio of Ni/Co in elec-trodeposition liquid, electrodeposition potential and electrodeposition time on hydrogen evolution property were investigated based on cathodic polarization curve (LSV). SEM images showed that nickel particles and nickel-cobalt alloy particles with grain size of about 100 nm were present on surfaces of pure nickel electrodes and Ni-Co alloy electrodes. The result of electro-chemical impedance spectroscopy (EIS) showed that electrical conductivity of Ni-Co alloy electrodes was superior to that of pure nickel electrodes. In addition, cathodic polarization curves indicated that hydrogen evolution potential of optimal Ni-Co al-loy electrode was 55 mV lower than that of pure Ni electrode at the current density of 30 mA/cm2, a nearly 20% decrease com-pared to that of pure Ni electrodes. Preparation method of Ni-Co alloy electrodes is simple, convenient and fast. Moreover, the hydrogen evolution property of Ni-Co alloy electrodes is much better than that of Ni electrodes. The optimum technological conditions are: NiSO4·6H2O: 27 g/L, CoSO4·7H2O: 3 g/L, H3BO3: 10 g/L, Na2SO4: 10 g/L, citric acid 10 g/L, sodium alkyl sulfate: 1 g/L, pH=4.0, electrodeposition potential:?1.3 V and electrodeposition time: 10 s.