Photocatalytic degradation of dyestuff wastewater under visible light irradiation using micron-sized mixed crystal TiO2 powders

✍ Scribed by Jun Wang; Ronghe Li; Zhaohong Zhang; Xiangdong Zhang; Wei Sun; Hao Wang; Rui Xu; Zhiqiang Xing

• Book ID: 102883094
• Publisher: Wiley (John Wiley & Sons)
• Year: 2007
• Tongue: English
• Weight: 599 KB
• Volume: 82
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.1709

✦ Synopsis

Abstract

A phase transformation of micron‐sized TiO~2~ powder from anatase to rutile was attempted by heat‐treatment in order to generate a new mixed crystal TiO~2~ with high associated photocatalytic activity. Heat‐treated micron‐sized TiO~2~ powders at different transition stages were characterized by X‐ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT‐IR) and transmission electron microscopy (TEM) methods. The tests of photocatalytic activity of the heat‐treated micron‐sized TiO~2~ powders were conducted by the photocatalytic degradation of Rhodamine B and Acid Red B under visible light irradiation. The results indicate that mixed crystal TiO~2~ photocatalyst heat‐treated at 400 °C for 60 min shows the highest photocatalytic activity. It can effectively decompose the Rhodamine B and Acid Red B in aqueous solution after 6 h visible light irradiation. A remarkable improvement in photocatalytic activity of TiO~2~ is caused by the formation of combined rutile–anatase phases and separation of photogenerated electron–hole pairs. Copyright © 2007 Society of Chemical Industry