Hydrogenation of magnesium nanoblades: The effect of concentration dependent hydrogen diffusion

By assuming the H diffusion coefficient and H adsorption rate to be exponentially and linearly dependent on concentration, a physical model is developed to predict the hydrogenation process of Mg nanoblades. The predicted H uptake curves agree well with the experimental data from V-coated Mg nanoblades. The obtained H diffusion coefficients in $MgHx$ between Mg and $MgH2$ have nearly three orders of magnitude variation. The characteristic time of H surface adsorption is longer than that of H diffusion in Mg but shorter than that in $MgH2$ for 100 nm thick nanoblades. A hydride shell is not formed during the hydrogenation.