论文部分内容阅读
采用溶体快淬法制备(Mg60Ni25)100-x Lax(x=4,6,8,10)的非晶贮氢合金带,分别采用X射线衍射仪和高分辨透射电镜对该合金在充放氢循环过程中的组织结构进行表征。结果表明:Mg65Ni27La8合金具有最高的放电容量(582 m A·h/g),充放电(吸释氢)过程可分为以下4个阶段:1)氢原子被非晶相吸收,氢原子的分布是无序的;2)随着吸氢过程的继续,合金中逐渐出现直径小于4 nm的HT-Mg2Ni H4和LT-Mg2Ni H4两种氢化物,且数量逐渐增加;3)随着氢化物开始分解释氢,分解后局部结构恢复到无序态,仅留下一些尺寸较大且较为稳定的LT-Mg2Ni H4纳米晶;4)剩余的氢原子从非晶相中释放,表现为非晶相的释氢,在此过程中合金的结构无显著变化。
(Mg60Ni25) 100-x Lax (x = 4, 6, 8, 10) amorphous hydrogen storage alloy ribbons were prepared by melt quenching method. The alloys were characterized by XRD and HRTEM. The organizational structure of the cycle is characterized. The results show that Mg65Ni27La8 alloy has the highest discharge capacity (582 m A · h / g). The charge-discharge (hydrogen absorption) process can be divided into the following four stages: 1) hydrogen atoms are absorbed by the amorphous phase, 2) As the hydrogen absorption process continues, two hydrides of HT-Mg2Ni H4 and LT-Mg2Ni H4 with diameter less than 4 nm gradually appear in the alloy and the number gradually increases; 3) As the hydride begins Decomposes and releases the hydrogen, the partial structure is restored to the disordered state after decomposition, leaving only some larger and more stable LT-Mg2NiH4 nanocrystals; 4) the remaining hydrogen atoms are released from the amorphous phase, showing an amorphous phase The release of hydrogen, the structure of the alloy in the process no significant change.