To tailor the hydrogen sorption properties of magnesium, improve its poor kinetics and alter its thermodynamics properties, sputtered multilayer Mg-based thin films were prepared in which Mg layers were confined by AlTi layers. Multilayer samples of different Mg thickness showed relatively long activation periods compared to the conventional co-sputtered alloys thin films. This activation period is attributed to the formation of voids and new surfaces which facilitate hydrogen transportation and its interaction with base metal. It has been found that the cyclability performance of materials is strictly connected to the stability of microstructure and resistance of multilayer structure to grain growth. At a certain Mg:AlTi thickness ratio (10:2), sintering of Mg layer could be prevented and long cyclability over 250 cycles has been achieved. Multilayers of few nm Mg thicknesses possess equilibrium pressures higher than pure Mg and the plateau pressure is a function of Mg thickness.
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