Structural, optical and electrical properties of transparent V and Pd-doped TiO2 thin films prepared by sputtering

Thin films of TiO2 doped with vanadium and palladium were prepared by the magnetron sputtering method. Important information about microstructure and band gap modification due to dopant incorporation in the TiO2 host lattice was provided by X-ray diffraction, optical transmission and electrical examinations. Three different phases were found in the thin film: (Ti,V)O2-solid solution, PdO and metallic inclusions of Pd. A band gap of (Ti,V)O2 of about 2.09 eV and an additional energy level of about 1.57 eV below conduction band was found from the absorption spectra. Negative sign of Seebeck coefficient indicates electronic conduction of the semiconducting Ti, V, Pd oxide composite