中國有色金屬學(xué)報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 22 Special 1 October 2012 |
（1. Institute of Applied Mechanics and Biomedical Engineering,
Taiyuan University of Technology, Taiyuan 030024, China;
2. Department of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, China;
3. Surface Engineering Institute, Taiyuan University of Technology, Taiyuan 030024, China）
Abstract:Nitrogen doped titanium dioxide (N-TiO2) coatings were fabricated by oxidation of the TiNx coatings in air. TiNx coatings were prepared on stainless steel (SS) substrates by plasma surface alloying technique. The reference TiO2 sample was also deposited by oxidation of the Ti coatings in air. The as-prepared coatings were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and ultra violet-visible absorption spectroscopy (UV-Vis). The formation of anatase type TiO2 is confirmed by XRD. SEM measurement indicates a rough surface morphology with sharp, protruding modules after annealing treatment. The band gap of the N-doped sample is reduced from 3.25 eV to 3.08 eV compared with the undoped one. All the N-doped samples show red shift in photoresponse towards visible region and improved photocurrent density under visible irradiance is observed for the N-doped samples. The photocatalytic activity was evaluated via the photocatalytic oxidation of methylene blue (MB) in aqueous under visible light irradiation. The results reveal that the N-doped samples extend the light absorption spectrum toward the visible region. The degradation rate of N-TiO2 is 20% in visible irradiation for 150 min.
Key words: TiO2; N doping; photocatalysis; stainless steel; plasma alloying
