La-Mg-Ni基合金储氢性能的研究

Study on Hydrogen Storage Characteristics of La-Mg-Ni Based Alloy

采用高频感应熔炼制备La0.7Ca0.3Ni2.8-xMgx(x=0.1、0.2、0.3、0.4)合金,进行X射线衍射(XRD)实验,气相储氢性能测试和电化学性能测试,分析Mg部分替代Ni对合金的储氢和电化学性能的影响。分析结果表明,合金具有多相结构,当x=0.1、0.3时,合金的主相是CaCu5-型结构的LaNi5相,当x=0.2、0.4时,合金的主相是AB2-型Laves相LaNi2相。随x=0.1、0.2、0.3、0.4合金电极的放电容量(mAh/g)依次为244.7、140.8、257.6、164。当x=0.1时,在2MPa氢压、25℃时,合金La0.7Ca0.3Ni2.7Mg0.1的储氢量达到1.1wt%。

The effect of substituting Ni with Mg in La0.7Ca0. 3Ni2.8-xMgr alloy on the hydrogen storage and the electrochemical properties were investigated. XRD analysis shows that the alloys consist of multf-phases. The main phase of La0.7Ca0.3Ni2.8-xMgr alloy （x=0. 1,0. 3） is LaNis phase with a hexagonal CaCus-type structure. The main phase of La0.7Ca0. 3Ni2.8-xMgr（x= O. 20. 4） is LaNi2 phase with AB2-type laves phase. Electrochemical experimental results show that when x= 0. 1,0. 2,0.3 and 0.4 the discharge capacities of the alloy electrodes are 244.7,140. 8,257.6 and 164 mAh/g, respectively. The P C isotherms experimental results absorption capacities of the La0.7 Ca0.3Ni2.7 Mg0.1 alloy is 1. lwt%at pressure. show that the hydrogen 25℃ and 2MPa hydrogen pressure.