金属氢化物电极表面处理方法及其表面氧化膜研究 Ⅰ.富镍表面处理及氧化膜的光电化学方法研究

The Investigations of Surface Treatment Methods and Characterization of Oxide Films on AB_5based Metal Hydride Electrodes Ⅰ. New Nirich treatment methods and photoelectrochemical characterization of oxide films

发展了两种贮氢合金表面处理新方法．光电子能谱和循环伏安实验表明，经过处理后得到了富镍表面层，可提高电极的反应性能．采用光电化学方法对不同处理的电极表面由动电位氧化形成的氧化膜进行了表征，分别观察到与表面膜吸附氢氧化和氧化还原反应有关的阳极光电流和阴极光电流，同时依照电极在循环过程中的光电流变化区分了两种处理方法所得到的表面层抗氧化性能之差异．通过粉末单电极初期充放电实验，证实了电极经方法１处理以后其放电性能得到提高．

Two simple and efficient surface treatment methods for AB_5type hydrogen storage alloys were developed. The results of X-ray photoelectron spectroscopy (XPS) and cyclic voltammetric (CV) experiments showed that the hydrogen storage alloys treated by two different methods had Nirich surface layer so that the performances of the electrodes were improved after treatment. The characterization of the oxide films which formed on the surface of electrodes through potentiodynamic oxidation with the help of photoelectrochemical microscopy (PEM) were done. The anodic photocurrent and the cathodic photocurrent related to the oxidation of hydrogen and the reduction of oxygen on the surface layer were observed in different potential regions respectively. Furthermore, it was found that the capability of oxidationresist of alloy depends on the surface treatment procedure, and it was shown that the capability of oxidationresist of alloy treated by the 1st method was better than the second. Finally, it was demonstrated that the discharge performance of the electrode treated by the 1st method was greatly improved.