Hydrogen storage properties of mechanical milled MgH2-nano Ni for solid hydrogen storage material

Among the metal hydrides, magnesium has the theoretically highest weight capacity for hydrogen storage (7.6 wt.%), lightweight and a reasonably low cost. However, high working temperature (>300°C), slow reaction kinetics (need more than 1 hour to produce 5 wt% of hydrogen) and difficult activation limit the practical application of Mg-based hydrides. In order to improve their performance, MgH₂ was catalyzed with Ni nanoparticles which reactively milled under hydrogen atmosphere. Phase identification and microstructure were characterised by XRD and scanning electron microscope (SEM). Hydrogen sorption properties was studied by gravimetric analysis method. The results showed that, small amount of Ni in nanometer scale proved to be as a suitable catalyst for improvement the kinetics of MgH₂ and at the same time allowed to reduce the milling time process. (paper)