Improvement of photo‐functional properties of TiO2 thin film coated by W surface layer

Abstract

AbstractTiO2 thin films with a W layer to improve photo‐functional properties were prepared using the reactive magnetron sputtering method. The W thin films at a thickness of 0.4 to 2.5 mm were coated onto the TiO2 thin films using the same magnetron sputtering. The surface chemical state of the W‐coated TiO2 thin films measured by X‐ray photoelectron spectroscopy showed W metal and/or W oxide on the TiO2 thin film. A spectrophotometer was used to investigate UV‐Vis absorption of the W‐coated TiO2 thin films which absorb energy of longer wavelength than the TiO2 thin film without the W surface layer. Visible‐light photocatalysis of the W‐coated TiO2 thin films was improved by four points in the sample with a W layer thickness of 1.7 nm, and photoconductivity was improved by four times under an artificial sun lamp. It is demonstrated that these improvements in the photo‐functional properties were achieved by a different cause. © 2013 Wiley Periodicals, Inc. Electron Comm Jpn, 96(3): 45–52, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11409