Synergetic effect of multiple phases on hydrogen desorption kinetics and cycle durability in ball milled MgH2–PrF3–Al–Ni composite

A new MgH 2 –PrF 3 –Al–Ni composite was prepared by ball milling under hydrogen atmosphere. After initial dehydrogenation and rehydrogenation, Pr 3 Al 11 , MgF 2 , PrH 3 and Mg 2 NiH 4 nanoparticles formed accompanying the main phase MgH 2 . The hydrogen absorption-desorption properties were measured by using a Sieverts-type apparatus. The results showed that the MgH 2 –PrF 3 –Al–Ni composite improved cycle stability and enhanced hydrogen desorption kinetics. The improvement of hydrogen absorption-desorption properties is ascribed to the synergetic effect of the in situ formed Pr 3 Al 11 , MgF 2 , PrH 3 and Mg 2 NiH 4 nanoparticles. This work provides an important inspiration for the improvement of hydrogen storage properties in Mg-based materials.