Hydrogen storage properties of nanocomposite Mg–Ni–Cu–CrCl3 prepared by mechanical alloying

The hydrogen storage properties of nanocomposite Mg–2Ni–2Cu–1CrCl3 (wt.%) prepared by mechanical alloying have been investigated. The ball milling process was performed under hydrogen atmosphere. During the ball milling process, the composite Mg–2Ni–2Cu–1CrCl3 can absorb hydrogen. When the ball milling time exceeds 110 h, the composite can absorb hydrogen completely (to its maximum). The nanocomposite has remarkable kinetics of hydriding/dehydriding process, for example, the nanocomposite milled for 110 h can absorb 5.5 wt.% hydrogen at 200 °C or 6.2 wt.% at 250 °C in 60 s under 2.0 MPa hydrogen pressure, and its desorption capacity also exceeds 6.3 wt.% in 700 s at 320 °C under 0.1 MPa. The influences of ball milling times on hydrogen storage properties were investigated. The catalytic effect of CrCl3 on the hydriding and dehydriding process was also discussed.