Synergistic effect of Ti and F co-doping on dehydrogenation properties of MgH2 from first-principles calculations
Synergistic effect of Ti and F co-doping on dehydrogenation properties of MgH2 from first-principles calculations
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DOI：
10.1016/j.jallcom.2012.05.098
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发表时间：
2012-10
影响因子：
6.2
通讯作者：
J. Zhang;Yangqiang Huang;C. Mao;P. Peng
中科院分区：
文献类型：
--
作者：
J. Zhang;Yangqiang Huang;C. Mao;P. Peng
采用基于密度泛函理论的第一性原理计算方法研究了Ti和F共掺杂mgh2的能量和电子性质。计算结果表明，相对于Ti原子单独掺入mgh2晶格，Ti原子与F原子结合的掺入在能量上是有利的。脱氢后，mgh2中共掺杂Ti和F较好地分别生成tih2和MgF2。相比之下，Ti和F对mgh2脱氢性能的改善效果优于纯Ti。这些结果为实验观察提供了合理的解释。电子结构分析表明，掺杂mgh2脱氢性能的增强可归因于外源物质掺杂削弱了Mg和H之间的键相互作用。
The energetic and electronic properties of MgH2co-doped with Ti and F are investigated using first-principles calculations based on density functional theory. The calculation results show that incorporation of Ti combined with F atoms into MgH2lattice is energetically favorable relative to single incorporation of Ti atom. After dehydrogenation, the co-doped Ti and F in MgH2preferably generate TiH2and MgF2, respectively. Comparatively, the combined effect of Ti and F in improving the dehydrogenation properties of MgH2is superior to that of pure Ti. These results provide a reasonable explanation for experimental observations. Analysis of electronic structures suggests the enhanced dehydrogenation properties of doped MgH2can be attributed to the weakened bonding interactions between Mg and H due to foreign species doping.