(1. 重庆师范大学 化学学院,重庆 400047;
2. 重庆大学 材料科学与工程学院,重庆 400044)
摘 要: 以NH4VO3、Al等为原料采用自蔓延高温法制备了钒基固溶体型贮氢合金V3TiNi0.56Al0.2,研究了V3TiNi0.56Al0.2贮氢合金的组织结构和电化学性能。结果表明:铸态贮氢合金V3TiNi0.56Al0.2的最大放电容量为350 mA∙h/g,活化性能较好,但氢的扩散系数小,循环性能和高倍率放电能力差。合金失去活性的原因是循环过程中钒基固溶体主相不断溶解到电解液中,通过真空熔炼处理可以改善合金的循环性能和高倍率放电性能。
关键字: 钒基固溶体贮氢合金;自蔓延高温合成;电化学性能
hydrogen storage materials
(1. College of Chemistry, Chongqing Normal University,Chongqing 400047, China;
2. College of Material Science and Engineering, Chongqing University,Chongqing 400044, China)
Abstract:The storage hydrogen alloy V3TiNi0.56Al0.2 was prepared by self-propagating high-temperature synthesis (SHS). The microstructure and electrochemical properties of alloy were investigated from the viewpoint of experiments. The results show that the maximal discharge capacity of as-cast alloy V3TiNi0.56Al0.2 is 350mA∙h/g. The activation performance is relatively good, the diffusion coefficient of the hydrogen is little, while the cyclic and discharge capacity are not good. The reason why the alloy lost the activity is that the main phase of vanadium-based solid solution alloy is dissolved in the electrolyte during cyclic course. The cyclic and discharge capacity could be improved by vacuum melting manage.
Key words: V-based solid solution hydrogen storage alloy; SHS; electrochemical properties