Hydrogen desorption properties of MgH 2 nanocomposites with nano-oxides and Inco micrometric- and nanometric-Ni

Abstract

The effects of doping with 5 wt.% of nano-oxides (n-Al 2O 3 and n-Y 2O 3), specialty Inco micrometric- and nanometric-Ni (m- and n-Ni) and their equal weight ratio mixtures on the hydrogen desorption properties of commercial MgH 2 were studied. The powder mixtures were mechanically milled for 20 and 100 h. Doping with n-Al 2O 3 does not have a beneficial effect and doping with n-Y 2O 3 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 H 2 pressure and substantially reduced apparent activation energies of desorption. Prolonged milling for 100 h is detrimental for the hydrogen storage properties of the MgH 2 doped with the specialty Inco m- and n-Ni.