Optical and morphological characterization of photocatalytic TiO2 thin films doped with silver

Silver-doped titanium dioxide thin films were deposited on glass substrates by the sol–gel process. Undoped films and films doped with 1 and 3 mol% Ag were annealed at 100 or 500 °C. The optical and morphological properties of the films were analyzed by optical absorption spectroscopy and scanning electron microscopy. Additionally, the films were evaluated for their ability to degrade methylene blue. It was found that the photocatalytic activity is barely sensitive to silver doping for films annealed at 100 °C, whereas the effect of silver resulted in enhanced photocatalytic activity for films annealed at 500 °C. For the latter annealing temperature, the photocatalytic activity increased with increasing Ag doping concentration.