中国物理B ›› 2011, Vol. 20 ›› Issue (1): 17102-017102.doi: 10.1088/1674-1056/20/1/017102

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Electronic structures and thermodynamic stabilities of aluminum-based deuterides from first principles calculations

叶小球, 罗德礼, 桑革, 敖冰云   

  1. Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621907, China
  • 收稿日期:2010-05-12 修回日期:2010-09-14 出版日期:2011-01-15 发布日期:2011-01-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 20971114).

Electronic structures and thermodynamic stabilities of aluminum-based deuterides from first principles calculations

Ye Xiao-Qiu(叶小球)†, Luo De-Li(罗德礼), Sang Ge(桑革), and Ao Bing-Yun(敖冰云)   

  1. Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621907, China
  • Received:2010-05-12 Revised:2010-09-14 Online:2011-01-15 Published:2011-01-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 20971114).

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摘要： The alanates (complex aluminohydrides) have relatively high gravimetric hydrogen densities and are among the most promising solid-state hydrogen-storage materials. In this work, the electronic structures and the formation enthalpies of seven typical aluminum-based deuterides have been calculated by the plane-wave pseudopotential method, these being AlD3, LiAlD4, Li3AlD6, BaAlD5, Ba2AlD7, LiMg(AlD4)3 and LiMgAlD6. The results show that all these compounds are large band gap insulators at 0 K with estimated band gaps from 2.31 eV in AlD3 to 4.96 eV in LiMg(AlD4)3. The band gaps are reduced when the coordination of Al varies from 4 to 6. Two peaks present in the valence bands are the common characteristics of aluminum-based deuterides containing AlD4 subunits while three peaks are the common characteristics of those containing AlD6 subunits. The electronic structures of these compounds are determined mainly by aluminum deuteride complexes (AlD4 or AlD6) and their mutual interactions. The predicted formation enthalpies are presented for the studied aluminum-based deuterides.

Abstract: The alanates (complex aluminohydrides) have relatively high gravimetric hydrogen densities and are among the most promising solid-state hydrogen-storage materials. In this work, the electronic structures and the formation enthalpies of seven typical aluminum-based deuterides have been calculated by the plane-wave pseudopotential method, these being AlD3, LiAlD4, Li3AlD6, BaAlD5, Ba2AlD7, LiMg(AlD4)3 and LiMgAlD6. The results show that all these compounds are large band gap insulators at 0 K with estimated band gaps from 2.31 eV in AlD3 to 4.96 eV in LiMg(AlD4)3. The band gaps are reduced when the coordination of Al varies from 4 to 6. Two peaks present in the valence bands are the common characteristics of aluminum-based deuterides containing AlD4 subunits while three peaks are the common characteristics of those containing AlD6 subunits. The electronic structures of these compounds are determined mainly by aluminum deuteride complexes (AlD4 or AlD6) and their mutual interactions. The predicted formation enthalpies are presented for the studied aluminum-based deuterides.

Key words: hydrogen storage material, complex aluminohydrides, electronic structures, density functional theory

中图分类号:  (Density functional theory, local density approximation, gradient and other corrections)

  • 71.15.Mb
71.15.Nc (Total energy and cohesive energy calculations) 71.20.Dg (Alkali and alkaline earth metals)