表面包覆镍处理La_(0.67)Mg_(0.33)Ni_(2.5)Co_(0.5)贮氢合金电极的电化学性能  

Effects of Ni-P Coatings on the Electrochemical Properties of the La_(0.67)Mg_(0.33)Ni_(2.5)Co_(0.5)Hydrogen Storage Alloy Electrode

作　　者：朱春玲[1] 阎汝煦[1] 王大辉[1] 康龙[1] 章应[1] 罗永春[1] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,甘肃兰州730050

出　　处：《稀有金属材料与工程》2006年第4期573-576,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金项目(50171021)

摘　　要：研究了表面包覆Ni-P对PuNi3型贮氢合金La0.67Mg0.33Ni2.5Co0.5电极的电化学性能的影响。结果表明:包覆镍处理改善了贮氢合金电极的循环稳定性。线性极化扫描和电化学阻抗谱等分析结果表明,包覆后合金电极的极限电流密度(Il),交换电流密度(I0)以及电化学阻抗均有较好的改善,说明电荷转移和氢的扩散能力得到提高。经25次电化学循环后的电极合金金相观察和分析表明,包覆Ni-P处理没有有效抑制其粉化,这与该类型贮氢合金电化学吸氢时氢化物膨胀较大有关。The effects of Ni-P coatings on the electrochemical properties of La0.67Mg0.33Ni2.5Co0.5 hydrogen storage alloy electrode was studied. The kinetic properties of the alloy electrode were evaluated. The results show that the cycling stability of the electrode is improved. The Ni-P coated powder electrode is better than bare electrode in exchange current density 10, Limiting current density It, high rate dischargeability and hydrogen diffusion coefficient D. It is found that the surface microencapsulation is ineffective in prohibiting disintegration, main reason for which is probably ascribed to the larger expansion of the La0.67Mg0.33Ni2.5Co0.5 hydrogen storage alloy hydride.

关 键 词：PuNi3型贮氢合金 表面化学镀 NI-P 电化学性能 

分 类 号：TG174.44[金属学及工艺—金属表面处理]