First-principles study on lithium and magnesium nitrogen hydrides for hydrogen storage

[摘要] We have investigated the fundamental properties such as structural stability, heat of formation and electronic structure of lithium and magnesium nitrogen hydrides, LiNH2, Mg(NH2)(2) and Li2NH, by means of the first-principles calculations using highly precise all-electron full-potential linear augmented plane wave method. The heats of formation involved in the reactions Li2NH + H-2 <-> LiNH2 + LiH are estimated as -63 kJ/mol H-2 within generalized gradient approximation and -71 kJ/mol H-2 within local density approximation. Furthermore, we also obtain heats of formation concerning two elementary reactions given by an ammonia mediated model for H-2 desorption mechanism. (C) 2007 Elsevier B.V. All rights reserved.

[发布日期] 2007-10-31

[效力级别]  Proceedings Paper

[关键词] energy storage materials;solid state reactions;enthalpy;crystal structure;first-principles calculation