Catalytic effect of SrTiO3 on the hydrogen storage behaviour of MgH2

Abstract

Abstract The effects of SrTiO3 on the hydrogen storage properties of MgH2 have been studied for the first time. The onset dehydrogenation temperature of the MgH2-10 wt% SrTiO3 is found to be 275 °C, which is 55 °C lower as compared to the as-milled MgH2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled MgH2. Meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled MgH2 at 320 °C. The calculated Ea of the MgH2-10 wt% SrTiO3 is 109 kJ/mol, which is 26.3 kJ/mol lower than the calculated Ea of the as-milled MgH2. The SrTiO3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO3 is owing to its ability to change the physical structure of the MgH2 particles during the ball milling process.