物理化学学报 >> 2015, Vol. 31 >> Issue (3): 540-544.doi: 10.3866/PKU.WHXB201501131

催化和表面科学 上一篇    下一篇

β-Bi2O3修饰Bi2WO6光催化降解苯酚及其可能机理

李晓金, 盛珈怡, 陈海航, 许宜铭   

  1. 浙江大学化学系, 硅材料国家重点实验室, 杭州 310027
  • 收稿日期:2014-10-30 修回日期:2015-01-12 发布日期:2015-03-06
  • 通讯作者: 许宜铭 E-mail:xuym@zju.edu.cn
  • 基金资助:

    国家自然科学基金(21377110)和国家重点基础研究发展规划项目(973) (2011CB936003)资助

Improved Photocatalytic Degradation of Phenol over β-Bi2O3 Modified Bi2WO6 and Possible Mechanism

LI Xiao-Jin, SHENG Jia-Yi, CHEN Hai-Hang, XU Yi-Ming   

  1. State Key Laboaratory of Silicon, Departement of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
  • Received:2014-10-30 Revised:2015-01-12 Published:2015-03-06
  • Contact: XU Yi-Ming E-mail:xuym@zju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21377110) and National Key Basic Research Program of China (973) (2011CB936003).

摘要:

采用简单混合法制备了一系列Bi2O3/Bi2WO6复合光催化剂. 在紫外光降解水中苯酚的过程中, Bi2O3/Bi2WO6的光催化活性随Bi2O3含量的增加呈现先增大后减小的趋势. 当Bi2O3最佳负载量等于12.5% (质量分数, w)时, 该复合光催化剂的活性大约是单一Bi2WO6的4 倍. 固体样品表征表明, Bi2O3主要以β-Bi2O3存在, 复合光催化剂是Bi2O3和Bi2WO6的简单混合物. 此外, 在电催化氧化水的过程中, β-Bi2O3/Bi2WO6薄膜电极的光电流远大于β-Bi2O3和Bi2WO6薄膜电极的光电流之和. Bi2O3对Bi2WO6光催化的促进作用是由于前者接受后者的光生空穴, 提高Bi2WO6光生载流子的分离效率, 从而加快了O2的还原和苯酚的降解.

关键词: 氧化铋, 钨酸铋, 光催化, 电荷转移, 有机物降解

Abstract:

In this study, a series of Bi2O3-containing Bi2WO6 catalysts were prepared by a simple mixing method. We used the oxidation of phenol in water under UV light as a model reaction, and found that as the amount of Bi2O3 in the mixture increased, its photocatalytic activity increased, and then started to decrease. A maximum activity was observed with the catalyst containing 12.5% (mass fraction, w) of Bi2O3, about 4 times that of Bi2WO6. Solid characterization revealed that the composite was a mixture of β-Bi2O3 and Bi2WO6. The water oxidation photocurrent over the β-Bi2O3/Bi2WO6 thin film electrode was much larger than the sum of the photocurrents of the β-Bi2O3 and Bi2WO6 thin film electrodes. It is proposed that there is a valence hole transfer from Bi2WO6 to β-Bi2O3, which improves the charge separation efficiency, and consequently increases the rate of phenol degradation.

Key words: Bismuth oxide, Bismuth tungstate, Photocatalysis, Charge transfer, Organic degradation

MSC2000: 

  • O643