Effect of nanostructure Ni on the sorption properties of mechanical milled MgH2 for solid hydrogen storage materials

Among the metal hydrides, magnesium has the theoretically highest weight capacity for hydrogen storage (7.6wt.%), lightweight and a reasonably low cost. However, high working temperature (>300 degrees 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 show 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.