Structure and hydrogenation properties of the ternary alloys Ca2−xMgxSi (0 ≤ x ≤ 1)
Structure and hydrogenation properties of the ternary alloys Ca2−xMgxSi (0 ≤ x ≤ 1)
复制标题
三元合金Ca2−xMgxSi (0 ≤ x ≤ 1)的结构和加氢性能
DOI：
10.1016/j.jallcom.2007.01.018
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发表时间：
2007
影响因子：
6.2
通讯作者：
J. Rush
中科院分区：
文献类型：
--
作者：
Hui Wu;Wei Zhou;T. Udovic;J. Rush
通过高温真空处理球磨的CaH 2/MgH 2/Si混合物，合成了部分Mg取代的Ca 2Si合金（Ca 2 −xMgxSi，0≤x≤1）。中子衍射结果表明，Ca 2 −xMgxSi（0<x<1）样品不是单相固溶体，而是（1−x）Ca 2Si +xCaMgSi混合相。吸氢实验表明，虽然纯Ca_2Si（x=0）易分解，形成非晶态氢化物相，但纯CaMgSi（x=1）在7 MPa H_2和473- 573 K范围内不明显吸氢。因此，如等温线测量和中子振动光谱所证明的，中间组合物（0<x<1）的氢吸收行为由Ca 2Si组分主导。
Partially Mg-substituted Ca2Si alloys (Ca2−xMgxSi, 0≤x≤1) were synthesized via high-temperature evacuation of CaH2/MgH2/Si ball-milled mixtures. Neutron diffraction refinements showed that Ca2−xMgxSi (0<x<1) samples are not single-phase solid-solutions, but rather (1−x)Ca2Si+xCaMgSi mixed phases. Hydrogen absorption measurements indicated that, although pure Ca2Si (x=0) is readily hydridable and forms an unusual amorphous-hydride phase, pure CaMgSi (x=1) does not noticeably absorb hydrogen up to 7MPa H2and 473–573K. Thus, hydrogen absorption behaviors of the intermediate compositions (0<x<1) are dominated by the Ca2Si component, as evidenced by the isotherm measurements and neutron vibrational spectra.