钛基镍钴合金电极的制备及析氢性能  

Preparation and Hydrogen Evolution Performance of Ni-Co Alloy Electrode on Titanium Substrate

作　　者：闫巍[1] 余智勇[1] 宋海燕[1] 李新杰[1] 宋军杰[2] 

机构地区：[1]中国华能集团清洁能源技术研究院有限公司,北京102209 [2]苏州竞立制氢设备有限公司,江苏苏州215168

出　　处：《表面技术》2017年第4期222-227,共6页Surface Technology

基　　金：清能院基金项目(CERI/TY-CA-004-15B)~~

摘　　要：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/cm^2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:NiSO_4·6H_2O 27 g/L,CoSO_4·7H_2O_3 g/L,H_3BO_3 10 g/L,Na_2SO_4 10 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 electrodeposition 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 electrochemical 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 alloy electrode was 55 m V lower than that of pure Ni electrode at the current density of 30 mA/cm^2, a nearly 20% decrease compared 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.

关 键 词：镍钴合金 析氢 电沉积 交流阻抗 扫描电镜 

分 类 号：TG132.21[一般工业技术—材料科学与工程]