Effect of Si substitution for Al on the structural and hydrogenation properties of the Zintl phase alloy SrAl2
Effect of Si substitution for Al on the structural and hydrogenation properties of the Zintl phase alloy SrAl2
复制标题
DOI：
10.1016/j.jallcom.2009.05.130
复制
发表时间：
2009-10
影响因子：
6.2
通讯作者：
Yunfeng Zhu;Wei Zhang;F. Hua;Liquan Li
中科院分区：
文献类型：
--
作者：
Yunfeng Zhu;Wei Zhang;F. Hua;Liquan Li
本文采用Si部分取代Zintl相合金SrAl 2中的Al，并通过X射线衍射（XRD）、光学显微镜（OM）和氢化测试研究了SrAl 2 −xSix（x= 0.2，0.4，0.6，0.8和1.0）合金的结构和氢化性能。随着Si取代Al，合金中出现SrAlSi相，SrAl2−xSix（x= 0.2，0.4，0.6）合金均由SrAl2和SrAlSi相组成。当x从0.2增加到0.6时，SrAl2和SrAlSi的相丰度分别降低和增加。然而，当x=0.8和1.0时，合金由单一的SrAlSi相组成。在573K和3MPa氢压下进行了加氢反应的测定。随着Si取代量的增加，合金的吸氢能力降低，这是由于SrAlSi相的吸氢能力比SrAl2相小，吸氢速率慢。
In this paper, Al was partially substituted by Si in the Zintl phase alloy SrAl2and the structural and hydrogenation properties of the SrAl2−xSix(x=0.2, 0.4, 0.6, 0.8 and 1.0) alloys were studied by X-ray diffraction (XRD), optical microscopy (OM) and hydrogenation measurements. With the substitution of Al by Si, SrAlSi phase appears in the alloy and the SrAl2−xSix(x=0.2, 0.4, and 0.6) alloys are all composed of SrAl2and SrAlSi phases. The phase abundance of SrAl2and SrAlSi is decreased and increased, respectively, when x increases from 0.2 to 0.6. However, the alloy consists of a single SrAlSi phase when x=0.8 and 1.0. Hydrogenation measurements were made at 573K under 3MPa hydrogen pressure. The hydrogen absorption capacity is decreased with increasing the Si substitution for Al, which can be attributed to the smaller hydrogen absorption capacity and slower hydrogenation rate of SrAlSi phase than SrAl2phase.