フェムト秒レーザ照射による酸化チタン膜の光触媒機能変化 Variation of Photocatalytic Function of TiO_2 Film by Femtosecond Laser Irradiation
Titanium dioxide (TiO<SUB>2</SUB>) is functional ceramics and shows the photocatalytic function by ultraviolet light illumination. This photocatalytic function enables decomposition of organic matter such as bacteria, mold and odors. In our previous study, the TiO<SUB>2</SUB> film was darkened by the femtosecond laser irradiation and electrical resistance of the darkened film was decreased. In this study, we investigated variation of the photocatalytic function of the darkened TiO<SUB>2</SUB> films. The TiO<SUB>2</SUB> film was produced by aerosol beam irradiation. The wavelength, the pulse width and the repetition rate of the femtosecond laser were 775 nm, 150 fs and 1 kHz, respectively. The laser spot was scanned on the whole area of the TiO<SUB>2</SUB> film surface and the laser fluence was changed within the laser fluence regime in which the laser ablation was not caused and topography of the film surface was not varied. The photocatalytic function of the darkened TiO<SUB>2</SUB> films was evaluated in the acetaldehyde decomposition test. In the test, the films in acetaldehyde were illuminated with the UV and visible light sources, respectively. The acetaldehyde concentration was measured every hour during the illumination. The results of the test shows that the film had photocatalytic function by visible light illumination.
高温学会誌 37(6), 311-315, 2011-11-20
High Temperature Society of Japan