Mechanistic Study of Visible-Light-Induced Photodegradation of 4-Chlorophenol by TiO2−x Nx  (0.021<x<0.049) with Low Nitrogen Concentration. (17th July 2011)

• Record Type: Journal Article
• Authors: Shang, Guangfeng; Fu, Hongbo; Yang, Shaogui; Xu, Tongguang
• Other Names: Yu Jiaguo Academic Editor.
• Is Part Of: International journal of photoenergy. Volume 2012(2012)
• Publication Date: 2011-07-17
• Subjects: Photochemistry -- Periodicals; Photobiology -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Photochimie; Photobiologie; Chimie physique et théorique; Chemistry, Physical and theoretical; Photobiology; Photochemistry; Electronic journals; Periodicals; 541.35
• DOI: 10.1155/2012/759306
• Languages: English
• ISSNs: 1110-662X

Abstract

Abstract : TiO2− x N x ( 0.021 < x < 0.049 ) powders with low N-doping concentrations (0.021 < x < 0.049 ) were prepared by annealing commercial TiO2 (P-25) under an NH3 flow at 550°C. Regardless of UV or visible case, the photoactivities of the samples decreased as x increased, and TiO1.979 N0.021 showed the highest activity for the 4-chlorophenol (4-CP) decomposition under the visible-light irradiation. The visible-light response for N-doped TiO2 could arise from an N-induced midgap level, formed above the valence band (O 2p). Electron spin resonance (ESR) measurements and the radical scavenger technologies gave the combined evidence that the active species ( OH andO 2 − ) are responsible for the photodecomposition of 4-CP over TiO2− x N x ( 0.021 < x < 0.049 ) under the visible irradiation. A possible photocatalytic mechanism was discussed in detail.