INFLUENCE OF HEAT TREATMENT CONDITION ON PHOTOCATALYTIC PROPERTIES OF OXIDIZED TiN FILM

Abstract

Nitride doped titanium oxide ( TiOxNy ) is a photocatalytic material which acts under visible light, while conventional titanium oxide acts only in ultra violet light. In this study, we tried to make nitride doped titanium film by oxidizing of TiN film. The TiN films were deposited on the quartz substrate by DC magnetron sputtering. The film structure was analyzed by X-ray diffraction. The photocatalytic decomposing rate was measured using methylene blue solution under black light and fluorescent lamp. As a result, post annealing process after oxidizing process is unsuitable to realize a high photocatalytic activity for oxidized TiN . On the other hand, the samples oxidized in nitrogen rich atmosphere showed the obvious photocatalytic activity under visible light irradiation. This reason is that the oxidation of the film surface is controlled and nitrogen atom left in film surface by nitrogen gas supplying. In conclusion, oxidizing of TiN film in nitrogen rich atmosphere is suitable to realize a high photocatalytic activity.