Hydrogen desorption properties of MgH2 nanocomposites with nano-oxides and Inco micrometric- and nanometric-Ni

The effects of doping with 5 wt.% of nano-oxides (n-Al2O3 and n-Y2O3), specialty Inco micrometric- and nanometric-Ni (m- and n-Ni) and their equal weight ratio mixtures on the hydrogen desorption properties of commercial MgH2 were studied. The powder mixtures were mechanically milled for 20 and 100 h. Doping with n-Al2O3 does not have a beneficial effect and doping with n-Y2O3 has only a limited effect on the temperatures and hydrogen desorption kinetics while nanocomposites doped with specialty Ni show reduced hydrogen desorption temperatures, very fast desorption kinetics under 0.1 MPa H2 pressure and substantially reduced apparent activation energies of desorption. Prolonged milling for 100 h is detrimental for the hydrogen storage properties of the MgH2 doped with the specialty Inco m- and n-Ni.