摘要
采用感应熔铸+热处理的方法制备了La(0.67-x)(Ti/Zr)xMg0.33Ni2.5Co0.5合金。结构分析表明,合金由PuNi3型相、Ce2Ni7型相、MgCu4Sn型相和Ti-Ni或Zr-Ni合金相等组成;Ti/Zr元素在PuNi3型物相和Ce2Ni7型物相中没有固溶,而是单独以Ti-Ni和Zr-Ni合金的形式存在;随Ti和Zr含量的增多,合金中PuNi3型物相的单胞体积呈线性减小趋势。Ti和Zr元素的掺入提高了合金的吸放氢平台,降低了合金的贮氢量。电化学研究表明,Ti/Zr元素显著提高了合金电极的高倍率放电性能,但过量的Zr元素会恶化合金电极的电催化活性;Ti/Zr元素的掺入对合金电极循环稳定性有一定改善,但同时会降低合金电极的电化学放电容量。
La（0.67-x）（Ti/Zr）xMg0.33Ni2.5Co0.5（x=0-0.15） were prepared by induction melting and annealing treatment. The structure analysis of alloys shows that the alloys are composed of multiphase, such as PuNi3-type phase, Ce2Ni7-type phase, MgCu4Sn-type phase, Ti-Ni or Zr-Ni phase. Ti and Zr elements didn＇t exist in PuNi3-type phase and Ce2NiT-type phase, and formed the Ti-Ni alloy and Zr-Ni alloy, respectively. With the contents of Ti and Zr increasing, the unit cell volume of PuNi3-type phase in alloys presented a linear decrease. The addition of Ti/Zr element heightened the plateau pressure of hydride, improved the cyclic stability of alloy electrodes to some extent, and reduced the capacity of hydrogen storage. Electrochemical analysis shows that the discharge ability is improved obviously to a high rate with the addition of Ti/Zr element, but the superfluous Zr element can reduce the electrochemical catalysis.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2006年第6期900-904,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金项目(50171021)
兰州理工大学"特色研究方向资助计划"
关键词
贮氢合金
PuNi3型
合金结构
电化学性能
hydrogen storage alloy
PuNi3-type
phase structure
electrochemical properties
