Hydrogen storage in Ti, V and their oxides-based thin films

We have investigated the hydrogen storage ability and the effect of hydrogenation on structure and physical properties of Ti/V and their oxides-based thin films. A series of Ti–TiO₂ and VOx–TiO₂ thin films with different layer structures, geometries and thicknesses have been prepared by the sputtering technique on different (Si(111), SiO₂, C) substrates. For the Ti–TiO₂–Ti films up to 50 at.% of hydrogen can be stored in the Ti layers, while the hydrogen can penetrate without accumulation through the TiO₂ layer. A large hydrogen storage was also found in some V₂O₅–TiO₂ films. Hydrogen could also remove the preferential orientation in the Ti films and induce a transition of V₂O₅ to VO₂ in the films.