LaNi_(5-x)Al_x贮氢合金的研究

Development of Hydrogen Storage Alloy LaNi 5-x Al x

本研究用Ａｌ置换ＬａＮｉ５合金中的部分Ｎｉ，得到一系列ＬａＮｉ５－ｘＡｌｘ（ｘ＝０．１，０．３，０．５）贮氢合金。对这些合金的吸放氢热力学和动力学性能的实验研究表明，随着Ａｌ的加入及Ａｌ含量的增加，贮氢合金的平台氢压降低，吸氢量有所减少，而吸放氢速度有所增加。通过对合金及其氢化物晶体结构的ＸＲＤ分析，发现Ａｌ的加入并未使晶体结构类型发生变化，只是晶格常数变大；ＬａＮｉ５－ｘＡｌｘ合金吸氢后原晶体结构也未发生变化，但其晶格常数增加较大。

A series of hydrogen storage alloys LaNi 5-x Al x(x=0.1,0.3,0.5) are obtained by means of substitution of Al for a portion of Ni in the alloy LaNi 5.It can be found by measuring thermodynamic characteristics of the alloy that the drop of hydrogen equilibrium pressure and hydrogen absorptivity,and the increase of hydrogen absorption speed will take place with Al addition and increase of its amount.X-ray diffraction analyses of crystal lattice of the alloy and its hydride after absorbing hydrogen show that the crystal structure does not change with the addition of Al,but the lattice constant slightly increases.It is also noted that absorption of hydrogen does not change the crystal structare of the alloy LaNi 5-x Al x,but greatly increases its lattice constant.