Abstract:In this work, nitrogen doped titanium oxides (N-doped TiOx) films were deposited by sputtering the TiO2 target in N2/Ar gas mixture to control the doping amount of nitrogen accurately. In order to modify the resultant films, the samples were annealed in air where the temperature ranged from 300 to 600℃, then they were irradiated under visible-light (VIS) after being placed in dark. X-ray photoelectron spectroscopy (XPS) spectra results showed that chemical composition of the films underwent the formation of N-Ti-O (β-N) and hydroxyl due to nitrogen doped into TiOx lattice. And the content of hydroxyl increased with annealing temperatures increasing, which led to the better hydrophilicity. X-ray diffraction (XRD) was used to investigate the crystallinity of the films annealed at different temperature and the results showed that the amorphous films transformed into crystalline phase as a consequence of annealing. Scanning electron microscopy (SEM) results showed that the particle size became bigger with the higher temperature. Hydrophilicity was tested by contact angle meter. The results showed that water contact angle decreased with the raising heat treatment temperature due to the change of particle size and the content of –OH. Hydrophilicity was also influenced by storing process, and the water contact angles increased with time. Furthermore, the hydrophilicity of N-doped TiOx films increased under visible light (VIS) irradiation.