International Journal of Hydrogen Energy, Vol.43, No.45, 20801-20810, 2018
The catalytic effect of an inert additive (SrTiO3) on the hydrogen storage properties of 4MgH(2)-Na3AlH6
Investigations on the catalytic effects of a non-reactive and stable additive, SrTiO3, on the hydrogen storage properties of the 4MgH(2)-Na3AlH6 destabilized system were carried out for the first time. The Na3AlH6 compound and the destabilized systems used in the investigations are prepared using ball milling method. The doped system, 4MgH(2)-Na3AlH6-SrTiO3, had an initial dehydrogenation temperature of 145 degrees C, which 25 degrees C lower as compared to the un-doped system. The isothermal absorption and desorption capacity at 320 degrees C has increased by 1.2 wt% and 1.6 wt% with the addition of SrTiO3 as compared to the 4MgH(2)-Na3AlH6 destabilized system. The decomposition activation energy of the doped system is estimated to be 117.1 kJ/mol. As for the XRD analyses at different decomposition stages, SrTiO3 is found to be stable and inert. In addition to SrTiO3, similar phases are found in the doped and the un-doped system during the decomposition and dehydrogenation processes. Therefore, the catalytic effect of the SrTiO3 is speculated owing to its ability to modify the physical structure of the 4MgH(2)-Na3AlH6 particles through pulverization effect. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.