Hydrogen Sorption in Erbium Borohydride Composite Mixtures with LiBH4 and/or LiH

Inorganics

Torben R. Jensen¹  Seyed Hosein Payandeh GharibDoust¹  Matteo Brighi²  Radovan Černý²  Michael Heere³  Bjørn C. Hauback³  Magnus H. Sørby³  Christoph Frommen³ 

[1] Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, University of Århus, Langelandsgade 140, DK-8000 Århus C, Denmark;Laboratory of Crystallography, Department of Quantum Matter Physics, University of Geneva, Quai Ernest-Ansermet 24, Ch-1211 Geneva, Switzerland;Physics Department, Institute for Energy Technology, NO-2027 Kjeller, Norway;

关键词: borohydride;    rare earth element;    hydrogen storage;    decomposition;    solid state electrolyte;   

DOI  :  10.3390/inorganics5020031

来源: DOAJ

【 摘 要 】

Rare earth (RE) metal borohydrides have recently been receiving attention as possible hydrogen storage materials and solid-state Li-ion conductors. In this paper, the decomposition and reabsorption of Er(BH4)3 in composite mixtures with LiBH4 and/or LiH were investigated. The composite of 3LiBH4 + Er(BH4)3 + 3LiH has a theoretical hydrogen storage capacity of 9 wt %, nevertheless, only 6 wt % hydrogen are accessible due to the formation of thermally stable LiH. Hydrogen sorption measurements in a Sieverts-type apparatus revealed that during three desorption-absorption cycles of 3LiBH4 + Er(BH4)3 + 3LiH, the composite desorbed 4.2, 3.7 and 3.5 wt % H for the first, second and third cycle, respectively, and thus showed good rehydrogenation behavior. In situ synchrotron radiation powder X-ray diffraction (SR-PXD) after ball milling of Er(BH4)3 + 6LiH resulted in the formation of LiBH4, revealing that metathesis reactions occurred during milling in these systems. Impedance spectroscopy of absorbed Er(BH4)3 + 6LiH showed an exceptional high hysteresis of 40–60 K for the transition between the high and low temperature phases of LiBH4, indicating that the high temperature phase of LiBH4 is stabilized in the composite.

【 授权许可】

Unknown