Composite materials based on Ti and Ru oxides

Abstract

The interaction and the electronic state of the components in the RuO₂–TiO₂ film system, obtained by the sol–gel method from poly(butyl titanate) and ruthenium chloride, are considered. After the films had been heat-treated in air at 770 K a composite oxide film was formed, which is mostly a phase of solid solution of TiO₂ in RuO₂. Further annealing of the film in H₂ led to deterioration of the solid solution and partial reduction of both components, Ti⁴⁺ and Ru⁴⁺ions. Within the reduced system ruthenium in oxidation states 0–VIII was identified by XPS. Titanium appeared in the form of non-stoichiometric Ti_nO_{2n– 1}, oxides, mostly Ti₄O₇, but TiO and Ti₂O are also possible.