化学学报 ›› 2013, Vol. 71 ›› Issue (03): 421-426.DOI: 10.6023/A12100830 上一篇    下一篇

研究论文

CdSeTe NSs/TiO2NTs的制备及其光电催化还原CO2的应用

井华, 王祜英, 徐金凤, 睢晓娜, 胡海涛, 李培强, 尹洪宗   

  1. 山东农业大学化学与材料科学学院 泰安 271018
  • 投稿日期:2012-10-27 发布日期:2013-02-01
  • 通讯作者: 李培强,尹洪宗 E-mail:chem_carbon@yahoo.cn,pqli@sdau.edu.cn
  • 基金资助:

    项目受国家青年自然科学基金(No.21203114)及山东省优秀中青年科学家科研奖励基金(No.BS2012NJ008)资助.

CdSeTe NSs/TiO2 NTs Photoelectric Catalytic Reduction of CO2

Jing Hua, Wang Huying, Xu Jinfeng, Sui Xiaona, Hu Haitao, Li Peiqiang, Yin Hongzong   

  1. College of Chemistry and Material Science, Shandong Agricultural University, Tai'an 271018
  • Received:2012-10-27 Published:2013-02-01
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21203114) and the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province (No. BS2012NJ008).

利用水热法将CdSeTe纳米片组装到TiO2纳米管阵列上, 制得CdSeTe NSs/TiO2 NTs催化剂. 由扫描电子显微镜图(SEM)和高分辨透射电子显微镜图(HRTEM)可知, CdSeTe 呈片状均匀平行生长于TiO2 NTs上. X射线衍射(XRD)数据表明片状CdSeTe主要沿着(100)、(002)晶面生长. 由紫外可见漫反射光谱(UV-vis DRS)得到材料的能隙为1.48 eV, X射线光电子能谱(XPS)数据得到价带位置为1.02 eV. 对材料的光电催化还原性能测试发现, CdSeTe NSs/TiO2 NTs与基底TiO2 NTs相比, 光照时对CO2的电流密度明显提高. 利用气相色谱检测发现光电催化还原CO2的主产物为甲醇, 并对其还原机理从能带匹配理论、电子传输高效性和材料的稳定性三方面进行了解释.

关键词: CdSeTe, TiO2 NTs, 光电催化还原, CO2, 能带匹配

The TiO2 NTs was prepared by means of anodic oxidation method at the applied voltage of 20 V. The electrolyte consisted of 0.8 wt% NH4F, 1.6 wt% NaSO4, and 10 wt% PEG400. After 3 h anodization, it was rinsed with twice-distilled water and dried in a nitrogen stream. And then the amorphous TiO2 NTs were crystallized by annealing in oxygen atmosphere for 1.5 h at 500 ℃ at both heating and cooling rates of 1 ℃·min-1. Subsequently, the TiO2 NTs and CdSeTe precursor solution were placed in teflon-lined stainless reactor at 120 ℃ for 2 h. Then the CdSeTe modified TiO2 NTs were dried at 80 ℃, at last, the modified TiO2 NTs was treated at 500 ℃ for 2 h under nitrogen atmosphere with heating and cooling rate of 2 ℃·min-1. The catalyst of CdSeTe NSs/TiO2 NTs was gained finally. According to the SEM (Scanning electron microscope), TEM (Transmission electron microscopy) and HRTEM (High resolution transmission electron microscopy) testing, it showed that the CdSeTe was sheet morphology and grew on the TiO2 NTs surface parallelly. XRD (X-ray diffraction) characterization revealed that CdSeTe NSs had preferential orientation along the (100) and (002) direction. Measured by UV-vis DRS (Ultraviolet-visible diffuse reflection spectrum), it got the band gap of the as-prepared catalyst material, 1.48 eV. Processing XPS (X-ray photoelectron spectroscopy) data by Linear extrapolation, we got its valence band located at 1.02 eV. So we could deduce that the conduction band minimum (CBM) was located at -0.46 eV. Under light irradiation, the photoelectrocatalytic reduction performance for CO2 had a significant improvement compared with TiO2 NTs, it expressed as the great increase of reduction current density. In the photoelectrocatalytic reduction of CO2 process, methanol was the major product identified by gas chromatography, and the excellent reduction mechanism was explained from the following three aspects: energy band match, electron high transport ability and the stability of catalyst material.

Key words: CdSeTe, TiO2 NTs, PEC reduction, CO2, energy band match