Acta Chimica Sinica ›› 2012, Vol. 70 ›› Issue (23): 2412-2418.DOI: 10.6023/A12070472 Previous Articles     Next Articles

Article

负载型TiO2/SBA-15的制备及其光催化还原CO2性能

王会香a,b, 姜东a, 吴东a, 李德宝a, 孙予罕a   

  1. a 中国科学院山西煤炭化学研究所 煤转化国家重点实验室 太原 030001;
    b 中国科学院大学 北京 100049
  • 收稿日期:2012-07-26 出版日期:2012-12-14 发布日期:2012-11-02
  • 通讯作者: 姜东 E-mail: jdred@sxicc.ac.cn
  • 基金资助:
    项目受国家自然科学基金(No. 21003150);山西省自然科学基金(No. 2011011006-2)和煤转化国家重点实验室自主研究项目(No. 2011BWZ011)资助.

Synthesis of Supported TiO2/SBA-15 Catalysts and Their Performance on Photocatalytic Reduction of CO2

Wang Huixianga,b, Jiang Donga, Wu Donga, Li Debaoa, Sun Yuhana   

  1. a State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001;
    b University of Chinese Academy of Sciences, Beijing 100049
  • Received:2012-07-26 Online:2012-12-14 Published:2012-11-02
  • Supported by:
    Project supported by the National Natural Science Foundation of China (No. 21003150), the Natural Science Foundation of Shanxi Province (No. 2011011006-2) and Independent Research Foundation of the State Key Laboratory of Coal Conversion (No. 2011BWZ011).

TiO2/SBA-15 catalysts, TiO2 nanoparticles well dispersed on SBA-15 supporter, have been successfully obtained through a self-assembly aging, carboxylation and subsequent solvothermal process. Firstly, P123 (PEG-PPG-PEG), KCl, (2-cyanoethyl) triethoxysilane (CETES) and tetraethoxysilane (TEOS) were employed to form cyano-modified SBA-15 (CN/SBA-15) in 2.0 mol/L HCl solution by self-assembly aging method. Secondly, carboxyl-modified SBA-15 (COOH/SBA-15) was got through carboxylation treatment in 48% H2SO4 solution at 95℃ for 24 h. Finally, highly dispersed TiO2/SBA-15 catalysts were successfully synthesized via solvothermal method at 220℃ for 12 h using COOH/SBA-15 and tetrabutyl titanate (TB) as raw materials. In order to remove the organic compounds and improve the crystallization of TiO2, the obtained TiO2/SBA-15 catalysts then were filtrated, washed by absolute ethanol for three times, dried at 80℃ and calcined at 550℃ for 4 h. Notably, the self-assembly and carboxylation process produced large number of good dispersive carboxyl groups (COOH) on SBA-15, which could effectively anchored TB molecules on SBA-15 to promise the highly dispersion of TiO2 on SBA-15. The obtained TiO2/SBA-15 catalysts have been characterized by X-ray diffraction (XRD), Raman spectrum, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), nitrogen adsorption and UV-Visible diffuse reflectance spectroscopy (UV-Vis). Above results indicate that the TiO2/SBA-15 catalysts exhibit large specific surface area and TiO2 on SBA-15 supporter is anatase phase, they are both play important roles in photocatalytic application. In the current manuscript, the photocatalytic reduction of CO2 under UV light irradiation as a prober reaction was used to investigate the photocatalytic performance of TiO2/SBA-15 catalysts. It was found that the obtained catalysts performed high photocatalytic capacity for CO2 reduction, especially when the loading amount of TiO2 was around 16.5 wt% [n(COOH)/n(TB)=3], the methanol production got maximum which could reach 80 μmol/g-catalyst after 6 h UV light irradiation. Compared with the catalysts which synthesized through simple impregnation method, our TiO2/SBA-15 catalysts showed the higher activity in photocatalytic reduction of CO2, owing to the better dispersion and crystallization.

Key words: carboxyl-modified SBA-15, titanium dioxide, photocatalytic reduction of CO2