In-situ powder neutron diffraction study on the formation process of LaMg2NiH7
In-situ powder neutron diffraction study on the formation process of LaMg2NiH7
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DOI：
10.1016/j.ijhydene.2017.02.196
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发表时间：
2017-08
影响因子：
7.2
通讯作者：
Toyoto Sato;K. Ikeda;M. Matsuo;K. Miwa;T. Otomo;S. Deledda;B. Hauback;Guanqiao Li;S. Takagi
中科院分区：
文献类型：
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作者：
Toyoto Sato;K. Ikeda;M. Matsuo;K. Miwa;T. Otomo;S. Deledda;B. Hauback;Guanqiao Li;S. Takagi
用原位粉末中子衍射法研究了金属间化合物LaMg_2Ni在室温下形成由La~(3+)、2×−~(2+)、[NiD_4]_4~(−)和3×O~(2+)−组成的氢化物(重氢)LaMg_2NiD_7的过程。当压力低于0.001 Mpa时，少量的氢首先溶解在LaMg_2Ni晶格中形成LaMg_2NiD_(0.05)，并连续生成两个新的氢化物相(LaMg_2NiD_x1和LaMg_2NiD_x2)。此外，在LaMg2NiD7出现之前，已经形成了具有NiD1.9和NiD3.3个单元和间隙氢原子的LaMg2NiD4.6。从它们的布拉格峰位推算出氢含量x1和x2分别为0.05；x1；x2和4.6。在大约0.001℃的压力下，LaMg_2NiD_7开始成形。由于中间化合物具有与LaMg2Ni相似的金属原子骨架，我们揭示了LaMg2NiD7的形成是在保持LaMg2Ni的金属原子骨架的情况下，通过多个氢化物相进行的。
The formation process from the intermetallic compound LaMg2Ni to a complex hydride (deuteride) LaMg2NiD7composed of La3+, 2 × Mg2+, [NiD4]4−, and 3 × D−was investigated by in-situ powder neutron diffraction under deuterium gas pressure at room temperature. Below 0.001 MPa, small amount of deuterium was initially dissolved in the lattice of LaMg2Ni forming LaMg2NiD0.05and two new hydride phases (LaMg2NiDx1and LaMg2NiDx2) were continuously yielded. Furthermore, LaMg2NiD4.6with NiD1.9and NiD3.3units and interstitial deuterium atoms was formed prior to appearing of LaMg2NiD7. From their Bragg peak positions, the deuterium contentsx1, andx2 were inferred as 0.05 <x1 <x2 < 4.6. At approximately 0.001 MPa, LaMg2NiD7started forming. Since the intermediate deuterides had similar metal atomic framework of LaMg2Ni, we revealed that LaMg2NiD7formation proceeded through multiple deuteride phases with maintaining of the metal atomic framework of LaMg2Ni.