Addition of Mg–Nb oxides (e.g. MgNb2O6

Mg4Nb2O9

and Mg3Nb6O11) ameliorates H2 absorption/desorption kinetics of MgH2 as demonstrated in the current article. H2 desorption and absorption rates of the ball-milled MgH2 are evidently temperature-dependent

which points out that the prior rate increases with increasing temperature (593–673 K) and vice versa. Among the tested samples

MgH2 with Mg3Nb6O11 nanoparticles showed superior performance. The Johnson–Mehl–Avrami equation was employed to construct H2 desorption curves as well as find out reaction rate constants at different temperatures. The Arrhenius equation was fitted in the context to estimate the activation energy of the ball-milled MgH2 and MgH2/Mg3Nb6O11 mixtures; for example

the values obtained were 127 and 88 kJ·mol−1

respectively. In addition

a novel experimental setup combining a hydrogen detector with a differential scanning calorimeter was used to confirm the H2 desorption properties of the ball-milled nanoparticles discussed based on the kinetic argument.