International Journal of Hydrogen Energy, Vol.44, No.33, 18153-18158, 2019
Theoretical discovery of high capacity hydrogen storage metal tetrahydrides
Hydrogen energy is attractive energy carrier due to its high energy density, abundant, environmentally friendly and renewable etc. However, the search for the high capacity hydrogen storage material is still a great challenge. In addition, the hydrogen storage materials should have excellent catalytic activity and superior mechanical properties to meet dehydrogenation and transportation. Here, we report on a novel metal tetrahydride that can effectively improve the hydrogen storage capacity. We obtain two novel metal tetrahydrides: TiH4 and VH4 based on the phonon dispersion and thermodynamically, respectively. In particular, those metal tetrahydrides not only exhibit good dehydrogenation behavior but also show superior mechanical properties. We demonstrate that the high hydrogen storage capacity of those tetrahydrides derives from the alternative stacking of metal layer and hydrogen layer. However, the excellent dehydrogenation process is attributed to the van der Waals interaction between hydrogen layers. Finally, the thermodynamic properties of TiH4 and VH4 are discussed. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Hydrogen storage materials;Metal tetrahydrides;High storage capacity;Dehydrogenation;Thermodynamic properties