In this work, Ce-doped Ti
6Cr
14V
80 BCC hydrogen-storage alloys have been synthesized as catalysts to enhance the hydrogen-storage performance of MgH
2 based on its room-temperature activation features and excellent durability. The Ti
6Cr
14V
80Ce
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In this work, Ce-doped Ti
6Cr
14V
80 BCC hydrogen-storage alloys have been synthesized as catalysts to enhance the hydrogen-storage performance of MgH
2 based on its room-temperature activation features and excellent durability. The Ti
6Cr
14V
80Ce
1 alloy was pre-ball milled under a hydrogen atmosphere into a Ti
6Cr
14V
80Ce
1H
x hydride. Different amounts of the Ti
6Cr
14V
80Ce
1H
x hydride were incorporated into MgH
2 by ball milling to obtain the MgH
2 +
y wt%Ti
6Cr
14V
80Ce
1H
x (
y = 0, 3, 5, 10, 15) nano-composites. With an optimization doping of 10 wt%Ti
6Cr
14V
80Ce
1H
x, the initial dehydrogenated temperature was decreased to 160 °C. Moreover, the composite can rapidly release 6.73 wt% H
2 within 8 min at 230 °C. Also, it can absorb 2.0 wt% H
2 within 1 h even at room temperature and uptake 4.86 wt% H
2 within 10 s at 125 °C. In addition, the apparent dehydrogenated activation energy of the MgH
2 + 10 wt%Ti
6Cr
14V
80Ce
1H
x composite was calculated to be 62.62 kJ mol
−1 fitted by the JMAK model. The capacity retention was kept as 84% after 100 cycles at 300 °C. The ball milled Ti
6Cr
14V
80Ce
1H
x transformed from the initial FCC phase structure into a BCC phase after complete dehydrogenation and back into an FCC phase when fullly hydrogenated. A catalyst mechanism analysis revealed that the ‘autocatalytic effect’ originating in Ti
6Cr
14V
80Ce
1H
x plays a crucial role in boosting the de-/hydrogenation properties of MgH
2. This work provides meaningful insights into rational designs of nano-compositing with different hydrogen-storage alloy catalyzed MgH
2.
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