Hydrogen storage characteristics of Ti– and V–based thin films

Z. Tarnawski, N.-T.H. Kim-Ngan
2016 Journal of Science: Advanced Materials and Devices  
Series of thin films of single-, bi-and tri-layered structure consisting of Ti, V, TiO 2 and V 2 O 5 layer and/or mixed TieVeNi layer with different layer sequences and thicknesses were prepared by the sputtering technique on Si and SiO 2 substrates. The layer chemical composition and thickness were determined by a combined analysis of X-ray diffraction, X-ray reflectometry, Rutherford backscattering and optical reflectivity spectra. The films were hydrogenated at 1 bar at 300 C and/or at high
more » ... 0 C and/or at high pressures up to 100 bar at room temperature. The hydrogen concentration and hydrogen profile was determined by means of a secondary ion mass spectroscopy and N-15 Nuclear Reaction Analysis. The highest hydrogen storage with a concentration up to 50 at.% was found in the pure Ti layers, while it amounts to about 30 at.% in the metallic TieVeNi layers. A large hydrogen storage (up to 20 at.%) was also found in the V 2 O 5 layers, while no hydrogen accumulation was found in the TiO 2 layers. Hydrogen could remove the preferential orientation of the Ti films and induce a complete transition of V 2 O 5 to VO 2 .
doi:10.1016/j.jsamd.2016.05.003 fatcat:g26eabm5dvfepnm46lxifr75fu