Hydrogen storage properties of γ–Mg(BH4)2 modified by MoO3 and TiO2.

The reversible hydrogen desorption–absorption of γ–Mg(BH 4 ) 2 ball milled with MoO 3 and TiO 2 has been investigated. No mechanochemical interaction between γ–Mg(BH 4 ) 2 and TiO 2 was observed while for the 1:1 M ratio with MoO 3 , MoB 2 was formed. There was little difference in the properties of γ–Mg(BH 4 ) 2 and γ–Mg(BH 4 ) 2 ball–milled with 0.02 mol percent TiO 2 and MoO 3 . However, mixing in the same ratio γ–Mg(BH 4 ) 2 with TiO 2 and MoO 3 that had previously been subjected to high energy milling provided significant effects. For these materials, the DSC peaks appeared broader and were shifted to slightly lower temperatures, while the TPD peaks were decreased by ca. 20 °C, as compared to the pure γ–Mg(BH 4 ) 2 . Faster hydrogen desorption kinetics was observed for the γ–Mg(BH 4 ) 2 –MoO 3 mixture. The reversible hydrogen storage capacity of γ–Mg(BH 4 ) 2 –TiO 2 at 271 °C was found to be 2.4 wt% H 2 in the first cycle. [ABSTRACT FROM AUTHOR]