Composite materials based on Ti and Ru oxides
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 TinO2n– 1, oxides, mostly Ti4O7, but TiO and Ti2O are also possible.