物理化学学报 >> 2011, Vol. 27 >> Issue (09): 2160-2166.doi: 10.3866/PKU.WHXB20110913

电化学和新能源 上一篇    下一篇

BiVO4膜电极的制备及其光电化学性能

彭天右, 柯丁宁, 曾鹏, 张晓虎, 范科   

  1. 武汉大学化学与分子科学学院, 武汉 430072
  • 收稿日期:2011-04-06 修回日期:2011-06-05 发布日期:2011-08-26
  • 通讯作者: 彭天右 E-mail:typeng@whu.edu.cn
  • 基金资助:

    国家自然科学基金(20871096, 20973128), 教育部新世纪优秀人才计划(NCET-07-0637)及高校基本科研业务基金(2081003)资助

Preparation and Photoelectrochemical Performance of BiVO4 Film Electrode

PENG Tian-You, KE Ding-Ning, ZENG Peng, ZHANG Xiao-Hu, FAN Ke   

  1. College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072, P. R. China
  • Received:2011-04-06 Revised:2011-06-05 Published:2011-08-26
  • Contact: PENG Tian-You E-mail:typeng@whu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20871096, 20973128), Program for New Century Excellent Talents in University, China (NCET-07-0637), and Fundamental Research Funds for the Central Universities of China (2081003).

摘要: 以自制的BiVO4纳米粉制备膜电极, 采用电化学方法较系统地研究了退火温度和膜厚对BiVO4膜电极的光电化学行为和电子输运与复合的影响. 结果表明: 退火温度和膜厚对BiVO4膜电极的光电特性有显著的影响. 膜厚为6.75 μm时, BiVO4膜电极具有最佳的光电化学特性. 退火温度低于500 °C时, 膜电极的光电活性随着温度的升高而增强, 至500 °C时达到最大值; 此后膜电极内的体相缺陷明显增加, 导致其光电活性逐渐降低. BiVO4膜电极有良好的可见光光电转换效率, 并利用其单色光转换效率曲线计算得到BiVO4的带隙为2.36eV, 采用莫特-肖特基电化学法测得其平带电位为-0.7 V (vs Ag/AgCl). 上述结果为BiVO4光催化体系的优化提供了重要的参考.

关键词: BiVO4膜电极, 光电化学性能, 瞬态光电流谱, 平带电位

Abstract: A BiVO4 film electrode was prepared using a home-made BiVO4 nanopowder and the effects of annealing temperature and film thickness on its photoelectrochemical behavior, electron transport and recombination in the BiVO4 electrode were systematically studied by electrochemical techniques. Experimental results indicate that the annealing temperature and film thickness can significantly influence the photoelectrochemical characteristics of the BiVO4 electrode. At low annealing temperature (≤500 °C) the photoelectrochemical activity improved upon increasing the temperature and the optimal activity was obtained for the electrode annealed at 500 ° C. At high temperature (>500 ° C) the photoelectrochemical activity decreased because of a marked increase of bulk traps in the electrode. The BiVO4 electrode showed good photon-to-electron conversion efficiency under visible light and its bandgap was found to be 2.36 eV based on an incident monochromatic photon-to-electric conversion efficiency curve. The flat-band potential (Efb) of BiVO4 was determined to be -0.7 V (vs Ag/AgCl) by the Mött Schottky method. These results give an important reference for the optimization of the BiVO4 photocatalytic system.

Key words: BiVO4 film electrode, Photoelectrochemical performance, Transient photocurrent spectrum, Flat-band potential

MSC2000: 

  • O646