Hydrogen sorption properties of the nanocomposites Mg–Mg 2Ni 1− xCo x obtained by mechanical alloying

Abstract

The hydrogen absorption–desorption characteristics of magnesium composites containing 10 and 15 wt.% Mg 2Ni 1− x Co x ( x=0.1 and 0.3) obtained by mechanical alloying in an inert atmosphere have been investigated. A significant improvement of the hydriding kinetics of these composites has been established, the high absorption capacity being preserved even at temperatures below 573 K. The catalytic effect of the intermetallic additive on the hydriding of magnesium has been explained as due to the presence of Ni and Co clusters in the nanocomposites, the increase of the specific surface area during mechanical alloying and the formation of MgNi 2 and Mg 2NiH 4 phases.