物理化学学报 >> 2013, Vol. 29 >> Issue (02): 397-402.doi: 10.3866/PKU.WHXB201211161

催化和表面科学 上一篇    下一篇

偏硼酸锶催化剂光催化还原CO2合成CH4

郭丽梅1,2, 匡元江3, 杨晓丹1,2, 于彦龙1,2, 姚江宏1,2, 曹亚安1,2   

  1. 1 南开大学物理科学学院, 天津 300071;
    2 南开大学泰达应用物理学院, 弱光非线性光子学教育部重点实验室, 天津 300457;
    3 中国人民解放军镇江船艇学院维修训练中心, 江苏 镇江 212000
  • 收稿日期:2012-09-28 修回日期:2012-11-15 发布日期:2013-01-14
  • 通讯作者: 曹亚安 E-mail:caoyaan@yahoo.com
  • 基金资助:

    国家自然科学基金(51072082, 21173121)资助项目

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).

摘要:

采用溶胶-凝胶法制备出偏硼酸锶(SrB2O4)光催化剂. 紫外光催化还原CO2合成CH4(在液相水中)的实验证明: SrB2O4催化剂的光催化活性略高于TiO2(P25). 利用X射线电子衍射谱(XRD)、傅里叶变换红外(FTIR)光谱、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、荧光(PL)光谱和紫外-可见(UV-Vis)漫反射吸收光谱等技术, 研究了SrB2O4 催化剂的晶体结构、形貌和能带结构. 结果表明: SrB2O4 的价带为2.07 V (vs normalhydrogen electrode (NHE)), 低于(H2O/H+)的氧化还原电位Eredoxo (0.82 V (vs NHE)); 而导带为-1.47 V (vsNHE), 高于(CO2/CH4)的氧化还原电位Eredoxo (-0.24 V (vs NHE)). 因此, SrB2O4催化剂可以有效地光催化还原CO2生成CH4. 与TiO2(P25)相比, SrB2O4催化剂具有相对较高导带, 光生电子的还原能力强于TiO2(P25), 更有利于CH4的生成, 从而决定了SrB2O4催化剂光催化还原CO2合成CH4具有较高的光催化活性.

关键词: 偏硼酸锶, 光催化还原CO2, CH4, 氧化还原电位, 光催化活性

Abstract:

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

MSC2000: 

  • O643