AVS 52nd International Symposium
    Applied Surface Science Monday Sessions
       Session AS-MoP

Paper AS-MoP17
Effect of Nitrogen on the Preparation of High Quality TiO@sub2-X@N@subX@ Thin Films as a Photocatalyst

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Aspects of Applied Surface Science Poster Session
Presenter: T. Nezuka, Toyama University, Japan
Authors: K. Prabakar, Toyama University, Japan
T. Takahashi, Toyama University, Japan
T. Nezuka, Toyama University, Japan
T. Nakashima, Kashiwa Chuo High School, Japan
Y. Kubota, Yokohama City University, Japan
A. Fujishima, Kanagawa Academy of Science and Technology, Japan
Correspondent: Click to Email
Titanium dioxide (TiO@sub2@) has been a well-known photocatalytic material for the past few decades, but needs UV light, so the development of a photocatalyst sensitive in visible light irradiation condition is important for indoor use. The main approaches were substitutional doping of nitrogen, since the TiO@sub2-X@N@subX@ films absorbs visible light, we have decided to use the visible light active TiO@sub2-X@N@subX@ film for the development of photocatalysis under controlled deposition parameters. TiO@sub2-X@N@subX@ films were deposited on glass substrates by reactive magnetron sputtering with different Ar+O@sub2@ mixture (7:3, 8:2 and 9:1) as reactive gas at different nitrogen flow ratio. Interestingly, the absorbance spectrum of the TiO@sub2-X@N@subX@ revealed that that the amount of nitrogen doped in the TiO@sub2@ films is not influenced by the nitrogen gas flow ratio but greatly depends on the sputtering pressure and substrate temperature. The properties of the films, including crystallinity, surface morphology and light absorption capability are influenced by the sputtering pressure, substrate temperature and post deposition annealing. The absorption edge shift to the visible light region and the new absorption shoulder at around 430 nm were observed for the films deposited at 0.1 Pa and annealed at 400 ° C and that they were related to the nitrogen doping, since TiO@sub2@ does not absorb such visible light regions. The photocatalytic degradation of organic compounds were analyzed and discussed as a function of deposition parameters such as gas flow ratio, substrate temperature, sputtering pressures and source to target distance. The efficiency of the photocatalytic activity of the TiO@sub2-X@N@subX@ thin films are calculated at different light intensity, solution concentration and the results are discussed.