Correlation between electronic structure and photocatalytic properties of non-metal doped TiO2/ZrO2 thin films obtained by pulsed laser deposition method

TiO2/ZrO2 thin films doped with N, C and/or O were synthetized by pulsed laser deposition in low-pressure, chemically active gaseous mixtures. Photocatalytical activity of the obtained structures was studied against reduction of toxic bichromate ions. A direct correlation was observed between the presence of ZrO2, the type and level of doping with N, C and/or O, the absorption in UV and visible range and the efficiency of the reduction reaction. The best conversion was achieved in case of ZrO2(10%)/TiO2 films deposited in N2/CH4 (5:1) mixture at a total pressure of 1 mbar. An interpretation of the obtained results based upon XPS analyses is provided.