Effect of NbF5 on hydrogen absorption and desorption properties of PrMg12/Ni alloy

PrMg12+30 wt%Ni + x wt.%NbF5(x = 0, 3, 6, 9, 12) alloy was prepared by mechanical ball milling. The effects of NbF5 on the microstructure, kinetics and thermodynamic properties of PrMg12/Ni alloy were systematically studied. The results show that adding NbF5 promotes the increase of the degree of amorphous nanocrystallization and the formation of defects such as dislocation and lattice distortion. When NbF5 is added at 9 wt%, the maximum saturated hydrogen absorption capacity is 5.4 wt% and the shortest time required to reach 95% saturated absorption capacity is 44 s. The shortest time required for the alloy to reach 95% of saturated hydrogen desorption capacity is 1597 s at an addition of 3 wt%, and the smallest activation energy for hydrogen desorption is 90.1 kJ/mol. It can be suggested that the addition of a certain amount of NbF5 has a positive effect on improving the hydrogen absorption and desorption kinetics of PrMg12/Ni alloy.