title: Local defects enhanced dehydrogenation kinetics of the NaBH(4)-added Li-Mg-N-H system.
abstract: A mechanistic understanding on the enhanced kinetics of hydrogen storage in the NaBH(4)-added Mg(NH(2))(2)-2LiH system is provided by carrying out experimental investigations associated with first-principles calculations. It is found that the operating temperatures for hydrogen desorption of the Mg(NH(2))(2)-2LiH system are reduced by introducing NaBH(4), and the NaBH(4) species seems almost unchanged during dehydrogenation/hydrogenation process. First-principles calculations reveal that the presence of NaBH(4) in the Mg(NH(2))(2)-2LiH system facilitates the formation of Mg vacancies in Mg(NH(2))(2). The appearance of Mg vacancies not only weakens the N-H bonds but also promotes the diffusion of atoms and/or ions, consequently resulting in the improvement of the reaction kinetics of hydrogen desorption/absorption of the NaBH(4)-added Mg(NH(2))(2)-2LiH system. This finding provides us with a deep insight into the role played by NaBH(4) in the Li-Mg-N-H system, as well as ideas for designing high-performance catalysts for metal-N-H-based hydrogen storage media.
authors.affiliation: State Key Laboratory of Silicon Materials & Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China.
authors.forename: Chu
authors.initials: C
authors.lastname: Liang
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Jiang
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Wei
authors.forename: Mingxia
authors.initials: M
authors.lastname: Gao
authors.forename: Hongge
authors.initials: H
authors.lastname: Pan
authors.forename: Qidong
authors.initials: Q
authors.lastname: Wang