Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (06): 1319-1326.doi: 10.3866/PKU.WHXB201304012

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Effect of Designed Zr/Ti Molar Ratio on the Photocatalytic Activity of Sr-Zr-Ti Mixed Oxide Catalysts under Visible Light

HUANG Hai-Feng1, JIA Jian-Ming1, LU Han-Feng2, ZHANG Hong-Hua1, PAN Lie-Qun3   

  1. 1 College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China;
    2 Research Institute of Catalytic Reaction Engineering, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, P. R. China;
    3 Environmental Monitoring Station of Fuyang City, Fuyang 311400, Zhejiang Province, P. R. China
  • Received:2012-11-20 Revised:2013-04-01 Published:2013-05-17
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21107096).

Abstract:

A series of Sr-Zr-Ti (SZT) mixed oxide catalysts were prepared by a fractional-precipitation method. These photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and ultraviolet visible (UV-Vis) diffuse reflectance absorption spectra. Photocatalytic degradation of methylene blue was investigated to determine the photoactivity of the catalyst. It was shown that with a Zr/Ti ratio<1, the SZT mixed oxide catalysts showed improved photocatalytic activity. This was attributed to lattice defects creating active photocatalytic sites because of Zr4+ doping. For Zr/Ti ratios ≥1, the catalysts showed markedly improved photocatalytic activity because of new crystalline phases of SrZrO3 and TinO2n-1 (n=4, 9)that facilitated splitting and conduction for electron/hole. Typical SZT samples (Zr/Ti=4) showed the highest photocatalytic activity, with first-order reaction rate constant 13.5 times that of a SrTiO3 sample.

Key words: Visible light, Sr-Zr-Ti mixed oxide, Zr/Ti molar ratio, Photocatalytic degradation, Methylene blue

MSC2000: 

  • O644