Hydrogen storage properties of magnesium ultrafine particles prepared by hydrogen plasma-metal reaction

The magnesium ultrafine particles (UFPs) were prepared by hydrogen plasma-metal reaction (HPMR) method. The structural analysis of the UFPs sample before and after the hydrogen sorption was carried out by X-ray diffraction (XRD). The size distribution and morphology of the sample were observed by transmission electron microscopy (TEM). The magnesium UFPs can absorb hydrogen completely at 673 K in 40 bar hydrogen atmosphere in the first cycle and then can absorb hydrogen completely and quickly at 573, 623, and 673 K. The van’t Hoff equations for the absorption and desorption and the formation enthalpy and entropy of the hydride were obtained according to the results of the pressure–composition isotherm (P–C–T) measurement.