In this work, we have investigated the hydrogen release and uptake pathways storage properties of the MgH
2Na
3AlH
6 with a molar ratio of 4:1 and doped with 10 wt% of TiF
3 using a mechanical alloying method. The doped composite was found to have a significant reduction on the hydrogen release temperature compared to the un-doped composite based on the temperature-programme-desorption result. The first stage of the onset desorption temperature of MgH
2Na
3AlH
6 was reduced from 170 °C to 140 °C with the addition of the TiF
3 additive. Three dehydrogenation steps with a total of 5.3 wt% of released hydrogen were observed for the 4MgH
2Na
3AlH
6-10 wt% TiF
3 composite. The re/dehydrogenation kinetics of 4MgH
2Na
3AlH
6 system were significantly improved with the addition of TiF
3. Kissinger analyses showed that the apparent activation energy, E
A, of the 4MgH
2Na
3AlH
6 doped composite was 124 kJ/mol, 16 kJ/mol and 34 kJ/mol lower for un-doped composite and the as-milled MgH
2, respectively. It was believed that the enhancements of the MgH
2Na
3AlH
6 hydrogen storage properties with the addition of TiF
3 were due to formation of the NaF, the AlF
3 and the Al
3Ti species. These species may played a synergetic catalytic role in improving the hydrogenation properties of the MgH
2Na
3AlH
6 system.
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