Ameliorating the re/dehydrogenation behaviour of MgH2 by zinc titanate addition

Magnesium hydride (MgH 2 ) is the most feasible and effective solid-state hydrogen storage material, which has excellent reversibility but initiates decomposing at high temperatures and has slow kinetics performance. Here, zinc titanate (Zn 2 TiO 4 ) synthesised by the solid-state method was used as an additive to lower the initial temperature for dehydrogenation and enhance the re/dehydrogenation behaviour of MgH 2 . With the presence of Zn 2 TiO 4 , the starting temperature for the dehydrogenation of MgH 2 was remarkably lowered to around 290 & DEG;C-305 & DEG;C. In addition, within 300 s, the MgH 2 -Zn 2 TiO 4 sample absorbed 5.0 wt.% of H 2 and 2.2-3.6 wt.% H 2 was liberated from the composite sample in 30 min, which is faster by 22-36 times than as-milled MgH 2 . The activation energy of the MgH 2 for the dehydrogenation process was also downshifted to 105.5 kJ/mol with the addition of Zn 2 TiO 4 indicating a decrease of 22% than as-milled MgH 2 . The superior behaviour of MgH 2 was due to the formation of MgZn 2 , MgO and MgTiO 3 , which are responsible for ameliorating the re/dehydrogenation behaviour of MgH 2 . These findings provide a new understanding of the hydrogen storage behaviour of the catalysed-MgH 2 system. & COPY; 2023 Chongqing University. Publishing services provided by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ) Peer review under responsibility of Chongqing University