Synergetic effect of Ni and Nb2O5 on dehydrogenation properties of nanostructured MgH2 synthesized by high-energy mechanical alloying
Synergetic effect of Ni and Nb2O5 on dehydrogenation properties of nanostructured MgH2 synthesized by high-energy mechanical alloying
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DOI：
10.1016/j.ijhydene.2009.07.038
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发表时间：
2009-09-01
影响因子：
7.2
通讯作者：
Simchi, A.
中科院分区：
文献类型：
--
作者：
Simchi, Hamed;Kaflou, A.;Simchi, A.
Nanostructured MgH2-Ni/Nb2O5 nanocomposite was synthesized by high-energy mechanical alloying. The effect of MgH2 structure, i.e. crystallite size and lattice strain, and the presence of 0.5 mol% Ni and Nb2O5 on the hydrogen-desorption kinetics was investigated. It is shown that the dehydrogenation temperature of MgH2 decreases from 426 degrees C to 327 degrees C after 4 h mechanical alloying. Here, the average crystallite size and accumulated lattice strain are 20 nm and 0.9%, respectively. Further improvement in the hydrogen desorption is attained in the presence of Ni and Nb2O5, i.e. the dehydrogenation temperature of MgH2/Ni and MgH2/Nb2O5 is measured to be 230 degrees C and 220 degrees C, respectively. Meanwhile, the dehydrogenation starts at 200 degrees C in MgH2-Ni/Nb2O5 system, revealing synergetic effect of Ni and Nb2O5. The mechanism of the catalytic effect is presented. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.
