Graphene Supported MgNi Alloy Nanocomposite as a Room Temperature Hydrogen Storage Material – Experiments and Theoretical Insights

Abstract Experimental studies along with density functional theory (DFT) calculations have been performed to probe and understand the hydrogen storage properties of graphene supported MgNi alloy nanoparticles nanocomposites. The main highlight of the present work is that nanostructuring and alloying of Mg with Ni and its dispersion on graphene (MgNi/G) & nitrogen/boron doped graphene (MgNi/NG, MgNi/BG) resulted in a substantial enhancement in the hydrogen storage capacity. The hydrogen storage capacity measured at room temperature and at 3 MPa pressure for MgNi/G, MgNi/BG and MgNi/NG are ∼2.5 wt. %, 3.5 wt. % and 5.4 wt. % respectively. The large improvement in hydrogen storage capacity compared to the reported values of G (0.5 wt. %), BG (0.7 wt. %) and NG (0.9 wt. %) under the same experimental conditions is noteworthy. DFT calculations shed light on the adsorption mechanism underlying this enhanced hydrogen uptake capacity and corroborate the experimental results.