Increasing Hydrogen Density with the Cation-Anion Pair BH4−-NH4+ in Perovskite-Type NH4Ca(BH4)3

Energies

Pascal Schouwink¹  Fabrice Morelle²  Yolanda Sadikin¹  Yaroslav Filinchuk²  Radovan ჎rný¹ 

[1]Department of Quantum Matter Physics, Laboratory of Crystallography, University of Geneva, Quai Ernest-Ansermet 24, CH-1211 Geneva, Switzerland

[2] E-Mails:

[3]Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, Place L. Pasteur 1, 1348 Louvain-la-Neuve, Belgium

[4] E-Mails:

关键词: metal borohydride;    perovskite;    ammonium;    ammonia-borane;    protic-hydridic;    hydrogen storage;   

DOI  :  10.3390/en8088286

来源: mdpi

【 摘 要 】

A novel metal borohydride ammonia-borane complex Ca(BH₄)₂·NH₃BH₃ is characterized as the decomposition product of the recently reported perovskite-type metal borohydride NH₄Ca(BH₄)₃, suggesting that ammonium-based metal borohydrides release hydrogen gas via ammonia-borane-complexes. For the first time the concept of proton-hydride interactions to promote hydrogen release is applied to a cation-anion pair in a complex metal hydride. NH₄Ca(BH₄)₃ is prepared mechanochemically from Ca(BH₄)₂ and NH₄Cl as well as NH₄BH₄ following two different protocols, where the synthesis procedures are modified in the latter to solvent-based ball-milling using diethyl ether to maximize the phase yield in chlorine-free samples. During decomposition of NH₄Ca(BH₄)₃ pure H₂ is released, prior to the decomposition of the complex to its constituents. As opposed to a previously reported adduct between Ca(BH₄)₂ and NH₃BH₃, the present complex is described as NH₃BH₃-stuffed α-Ca(BH₄)₂.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.