Decomposition of Methylene Blue with Photocatalytic TiO_2 Thin Films Deposited by Pulsed Laser Deposition

摘要

Photocatalytic titanium dioxide (TiO_2) thin films with large specific surface area were deposited on Si wafers by pulsed laser deposition with sintered TiO_2 targets in oxygen gas atmosphere. Angular distributions of the number of droplets and the film thickness were examined. The surface roughness and the film thickness depended on the oxygen gas pressure. Photocatalytic effect of the films deposited at various substrate temperatures was evaluated by photobleaching of methylene-blue aqueous solution. The TiO_2 film deposited at the substrate temperature of 250°C was anatase-type crystal and this film indicated the highest photocatalytic effect.