Synthesis and reversible hydrogen storage property of novel FCC Mg0.8Sc0.2Hx prepared by high GPa pressure technique

A face centered cubic (FCC) type Mg-Sc hydride (Mg0.8Sc0.2Hx phase) was prepared by an ultra-high pressure (UHP) technique generating an 8 GPa hydrogen pressure. Reversible hydrogen releasing and restoring behaviors have been observed by a differential scanning calorimeter (DSC) measurement at a 0.5 MPa hydrogen pressure. The hydrogen releasing temperature was lower by around 70 K than that of MgH2. The structural analysis using a Rietveld refinement of the synchrotron X-ray diffraction patterns indicated that the FCC phase was preserved without decomposition after the reproducible hydrogen releasing and restoring reactions.