Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (7): 1399-1405.doi: 10.3866/PKU.WHXB201505191

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Preparation and Characterization of Sr/TiO2 Catalysts with Different Structures and High Photocatalytic Activity under Visible Light

JIANG Xiao-Jia1, JIA Jian-Ming1, LU Han-Feng2, ZHU Qiu-Lian2, HUANG Hai-Feng1   

  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, Zhejiang University of Technology, Hangzhou 310014, P. R. China
  • Received:2015-03-24 Revised:2015-05-18 Published:2015-07-08
  • Contact: HUANG Hai-Feng E-mail:hhf66@zjut.edu.cn
  • Supported by:

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

Abstract:

Sr/TiO2 catalysts with different Sr/Ti molar ratios (n(Sr)/n(Ti)) were synthesized by fractional precipitation. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectrometry, and ultraviolet-visible diffuse reflectance spectrophotometry (UV-Vis RDS). The photocatalytic activity of the samples under visible light was determined using the photocatalytic degradation of methylene blue. The photocatalytic activities and structures of the catalysts changed with n(Sr)/n(Ti) molar ratio. When n(Sr)/n(Ti)≤3/2, the catalysts, which were composed of TiO2 and SrTiO3, showed a globular structure. When n(Sr)/n(Ti) was between 3/2 and 4/1, the catalysts had a flaky structure. As the n(Sr)/n(Ti) increased, the composition of the catalysts changed from SrTiO3 and Sr24 to Sr24 and Sr(OH)2·H2O. When the n(Sr)/n(Ti) ratio was 9/1, the catalyst mainly consisted of Sr(OH)2 ·H2O and exhibited an acicular structure. The sample with n(Sr)/n(Ti)=4/1 exhibited the highest photocatalytic activity; its first-order reaction rate constant was 5.0 times as high as that of the perovskite catalyst SrTiO3 and 86.7 times as high as that of the commercial Ti photocatalyst P25.

Key words: Sr/Ti molar ratio, Different structure, Photocatalysis, Methylene blue, Visible light

MSC2000: 

  • O644