Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (02): 397-402.doi: 10.3866/PKU.WHXB201211161

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Photocatalytic Reduction of CO2 into CH4 Using SrB2O4 Catalyst

GUO Li-Mei1,2, KUANG Yuan-Jiang3, YANG Xiao-Dan1,2, YU Yan-Long1,2, YAO Jiang-Hong1,2, CAO Ya-An1,2   

  1. 1 College of Physics, Nankai University, Tianjin 300071, P. R. China;
    2 Teda Applied Physics School, Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, Nankai University, Tianjin 300457, P. R. China;
    3 Maintenance Training Center, Zhenjiang Watercraft College, Zhenjiang 212000, Jiangsu Province, P. R. China
  • Received:2012-09-28 Revised:2012-11-15 Published:2013-01-14
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51072082, 21173121).


The reduction of carbon dioxide to methane in the presence of water was used to evaluate the photocatalytic activity of a prepared strontium metaborate catalyst. The strontium metaborate (SrB2O4) was prepared by a simple sol-gel method, and was shown to exhibit better photocatalytic performance than TiO2 (P25) under UV-light irradiation. The structure, morphology, and energy levels of the photocatalysts were studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy, and UV-Vis diffuse reflectance absorption spectroscopy. It was revealed that the SrB2O4 valence band (VB) was located at 2.07 V (vs normal hydrogen electrode, NHE), which is more positive than Eredoxo (H2O/H+) (0.82 V (vs NHE)); the conduction band was estimated to be -1.47 V (vs NHE)), which is more negative than Eredoxo (CO2/CH4) (-0.24 V (vs NHE)). Therefore, it is clear that strontium metaborate is capable of transforming CO2 into CH4. Moreover, the potential at the bottom of the conduction band for SrB2O4 is more negative than that for TiO2(P25), leading to a higher deoxidization capacity, which also favors CH4 formation. Thus, SrB2O4 exhibits a higher photocatalytic activity than TiO2(P25).

Key words: Strontium metaborate, Photocatalytic reduction of CO2, CH4, Redox potential, Photocatalytic activity