J Mater Sci Technol ›› 2005, Vol. 21 ›› Issue (02): 191-195.

• Research Articles • Previous Articles     Next Articles

Preparation of (Ti, Sn)O2 Nano-Composite Photocatalyst by Supercritical Fluid Dry Combination Technology

Jingchang ZHANG, Qing LI, Weiliang CAO   

  1. Institute of Modern Catalysis, The Key Laboratory of Science and Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China
  • Received:2004-05-28 Revised:2004-06-14 Online:2005-03-28 Published:2009-10-10
  • Contact: Weiliang CAO

Abstract: A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%~30.1%) were prepared from TiCl4 and SnCl4•5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination technology. Characterizations with X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed that, in addition to anatase type TiO2, a new active phase (Ti, Sn)O2 (with particle size of 2.0~4.3 nm) formed, and there were no SnO2 crystals observed in the range of the doping concentration studied. Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts. Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method, Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity. The photo-catalytic degradation rate of phenol could reach as high as 93.5% after 7 h. The preparation conditions of the new phase (Ti, Sn)O2 were investigated and its catalytic mechanism was proposed. The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size, large surface area and high activity.

Key words: Anatase TiO2, (Ti, Sn)O2, Photo-catalytic, Supercritical fluid dry method, Solid-phase reaction