Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (05): 1149-1156.doi: 10.3866/PKU.WHXB20110520

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Preparation of F-Modified Nanosized TiO2 and Its Methyl Orange Photodegradation Mechanism

JIANG Jing-Jing, LONG Ming-Ce, WU De-Yong, CAI Wei-Min   

  1. School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
  • Received:2010-10-20 Revised:2011-03-01 Published:2011-04-28
  • Contact: LONG Ming-Ce E-mail:long_mc@sjtu.edu.cn
  • Supported by:

    The project was supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (20090073120042).

Abstract:

Fluorine-modified nanosized TiO2 (F-TiO2) was prepared by a facile precipitation-fluorination- reflux method. Characterizations of transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and diffuse reflectance spectroscopy (DRS) were carried out to investigate various properties of the as-prepared F-TiO2 powder. We found that the F-TiO2 particles were small (5-8 nm) and ellipsoidal in shape. The presence of fluorine not only suppressed the formation of a brookite phase, but also improved the crystallinity of the anatase phase. The fluorine atoms were mainly distributed on the surface of TiO2, and existed in both forms of chemical-adsorption and interstitial-doping. Compared to pure titania, the fluorine-modified TiO2 powder showed a much higher methyl orange (MO) degradation efficiency under UV light and under visible light. Through the experiments of alkaline washing and heat treatment, we found that the increased MO degradation rate under visible light irradiation was caused by the enhanced self- degradation of the dye over the surface-modified TiO2.

Key words: Fluorine-modification, Titanium dioxide, Reflux, Visible-light activity, Dye sensitization

MSC2000: 

  • O643