One-step uniform growth of magnesium hydride nanoparticles on graphene

A simple solvent-free method to synthesize MgH₂ nanoparticles (MgH₂ NPs) uniformly grown on graphene nanosheets (GNs) has been reported in this paper. Based on the formation of MgH₂ by di-n-butylmagnesium ((C₄H₉)₂Mg) thermal decomposition under hydrogen pressure, the GNs were added as matrix to hinder the agglomeration and growing of MgH₂ NPs. The fabricated MgH₂/GNs nanocomposites, in which MgH₂ NPs were homogenously growing in the graphene matrix, have been synthesized by the favorable adsorption energy between (C₄H₉)₂Mg and GNs. Resulting from the one-step solvent-free route, the generated MgH₂ NPs shows high hydrogen capacity and steady hydriding and dehydriding properties, without the interference of the synthetic medium. At the same time, the size of the fabricated MgH₂ NPs can be controlled by adjusting the mass ratio of MgH₂ to graphene, the various hydrogen pressure and temperature. Attributed to smaller size effect, well uniform distribution of high density MgH₂ NPs, and the agglomeration blocking ability of graphene, the MgH₂/GNs-40 wt% exhibits the favorite hydrogen storage performance.