rGOを担持したMg-Feの水素化特性の評価

抄録

Magnesium (Mg) has attracted attention because of its light weight, abundant resources, and large maximum hydrogen absorption capacity of 7.6 wt.%. This study investigated the hydrogen absorption-desorption properties of Mg-based hydrogen storage alloys with Fe and reduced graphene oxide (rGO), i.e., Mg-Fe, Mg-Fe-rGO-1, Mg-Fe-rGO-2 that were prepared by mechanical alloying. PCT curve measurements showed that hydrogen was absorbed and released from all samples at 280 ℃ and 250 ℃ and at the maximum hydrogen pressure of 0.99 MPa. Mg-Fe-rGO-1 showed the highest maximum hydrogen absorption of 5.23 wt.%, which was close to the maximum hydrogen absorption of 7.6 wt.% for Mg. DSC measurements showed that hydrogen was released from all samples, and the hydrogen release temperature was lower than that of commercial MgH₂. In particular, Mg-Fe-rGO-2 showed the lowest hydrogen desorption temperature. The hydrogen desorption temperature of Mg-Fe-rGO-1 was not reduced as much as that of the other samples because the catalytic effect of Fe and rGO was not fully demonstrated due to the many rGO defects generated during MA.