La_(1+x)Mg_(2-x)Ni_9(x=0,0.5,1.0,1.5)合金的储氢性能及电化学性能研究

Hydrogen Storage Capacities and Electrochemical Performances of La_(1+x)Mg_(2-x)Ni_9(x=0,0.5,1.0,1.5)Alloys

利用高频熔炼方法制备了La1+xMg2-xNi9(x=0,0.5,1.0,1.5)系列合金,并对其进行了XRD分析和储氢容量及电化学性能测定。结果表明:随着La含量增大,合金中LaNi5和(La,Mg)Ni3相转变为LaNi3相,且Mg2Ni相出现,晶胞体积也增大,合金的储氢容量和电化学性能提高;当x=1.5时,Mg2Ni相消失,合金的储氢性能有所下降。当x=1.0时,即La2MgNi9合金具有较好的储氢容量及电化学容量。

The La1＋xMg2-xNi9 （x-=0, 0.5, 1.0, 1.5） alloys were prepared in high frequency induction furnace under Ar atmosphere. The compositions and phase structures of the prepared alloys were analyzed by XRD method, and their hydrogen storage capacities and electrochemical performances were investigated. The results show that with La content increasing, LaNi5 and （La, Mg） Ni3 phases are transferred to LaNi3 phase, Mg2Ni phase appears, the cell volume increases, and the hydrogen storage capacity and electrochemical performance are improved. While x=1.5, Mg2Ni phase disappears, the hydrogen storage properties of La2.5Mg0.5Ni9 alloy are impaired. The hydrogen storage capacity and electrochemical performance of La2MgNi9 alloy are better than those of the other three alloys.