Visible light induced photodegradation of organic pollutants on nitrogen and fluorine co-doped TiO_2 photocatalyst

Article type: Research Article

Authors: WANG, Zheng-peng | XU, Jun | CAI, Wei-min | ZHOU, Bao-xue | HE, Zheng-guang | CAI, Chun-guang | HONG, Xiao-ting

Affiliations: School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China

Note: [] Corresponding author. E-mail: [email protected]

Abstract: The nitrogen and fluorine co-doped TiO_2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetrabutyl titanate with ammonium fluoride. Nitrogen and fluorine co-doping causes the absorption edge of TiO_2 to shift to a lower energy region. The photocatalytic activity of co-doped TiO_2 with anatase phases was found to be 2.4 times higher than that of the commercial TiO_2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation. The co-doped TiO_2 powders only contain anatase phases even at 1000°C. Apparently, ammonium fluoride added retarded phase transformation of the TiO_2 powders from anatase to rutile. The substitutional fluorine and interstitial nitrogen atoms in co-doped TiO_2 polycrystalline powder were responsible for the vis light response and caused the absorption edge of TiO_2 to shift to a lower energy region.

Keywords: photocatalyst, visible light, nitrogen and fluorine co-doped, phenol, band gap

Journal: Journal of Environmental Sciences, vol. 17, no. 1, pp. 76-80, 2005