Hydrogen storage properties of Mg-30 wt.% LaNi₅ composite prepared by hydriding combustion synthesis followed by mechanical milling (HCS + MM)

A Mg-30 wt.% LaNi₅ composite was prepared by hydriding combustion synthesis followed by mechanical milling (HCS + MM), and the hydriding and dehydriding properties of the HCS + MM product were compared with those of the HCS product and the MM product. The dehydriding temperature onsets of the MM and HCS + MM products were both 470 K, which were lower than that of the HCS product by 100 K. Moreover, the HCS + MM product desorbed faster than the MM product, e.g., the former desorbed completely upon heating to 510 K, whereas the latter did not decompose completely until 590 K. Additionally, the HCS + MM product reached a saturated hydrogen absorption capacity of 3.80 wt.% at 373 K in 50 s, but both the HCS product and the MM product absorbed less than 1.50 wt.% of hydrogen at 373 K in 1800 s. These results suggest the potential of the HCS + MM processing in preparing Mg-based hydrogen storage materials.