Hydrogen storage properties of MgH2-(Sr,Ca)2AlH7 composite

The hydrogen storage properties, phase components and surface characteristics of a newly designed MgH2-(Sr,Ca)2AlH7 composite doped with a little amount of TiF3 were studied in this paper. It was found that the MgH2-30 wt.% (Sr,Ca)2AlH7 composite doped with 2 mol% of TiF3 desorbed hydrogen quickly at 573 K. Moreover, it has a higher re-hydrogenation rate at the temperatures below 473 K under the hydrogen pressure of 1.0 MPa. The new Ti-contained species as well as the phases (Sr,Ca)F2, (Sr,Ca)H2 and (Sr,Ca)Al4 formed during the dehydrogenation process prior to the hydrogen uptake distributes homogeneously on the surface of Mg particles, and has a good catalytic effect on the re-hydrogenation process of Mg phase consequently.