X-ray Studies on partially decomposed γ- Mg(BH4)2

Abstract

Hydrogen is the energy that fuels the sun and the stars. Having the potential to be zero-carbon during production, when produced by renewable resources, it is an attractive carrier of the pollution-free renewable energy. In this context, magnesium borohydride (Mg(BH4)2) is recognized as an attractive potential hydrogen storage material due to its high hydrogen content and low H2 release temperature. Hydrogenation of completely decomposed Mg(BH4)2 requires high-temperature, high H2 pressure, and very long reaction time. Studies show that the partially decomposed Mg(BH4)2 can be hydrogenated in comparatively lower temperatures, pressure, and short reaction time but up to date, the reversible reaction shows only 2.5 wt% of H2 production which is not sufficient for its practical use. To achieve higher wt% of H2 it is important to understand the kinetics of the dehydrogenation and rehydrogenation of Mg(BH4)2 reactions and the nature of the reaction intermediates. The latter has been debated for more than 10 years. [...]