化学学报 ›› 2012, Vol. 0 ›› Issue (04): 405-410.DOI: 10.6023/A1107072 上一篇    下一篇

研究论文

TiO2 纳米管半波脉冲直流电光电催化还原Cr(VI)

汪青, 尚静, 宋寒   

  1. 北京大学环境科学与工程学院 环境模拟与污染控制国家重点联合实验室 北京 100871
  • 投稿日期:2011-07-07 修回日期:2011-09-15 发布日期:2011-10-09
  • 通讯作者: 尚静
  • 基金资助:

    国家自然科学基金(No. 20407002)、国家重点基础研究发展计划(973 计划) (No. 2002CB410802)及环境模拟与污染控制国家重点联合实验室(北京大学) 专项资助项目.

Photoelectrocatalytic Reduction of Cr(VI) over TiO2 Nanotube Arrays under Half-wave Pulsed Direct Current

Wang Qing, Shang Jing, Song Han   

  1. State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871
  • Received:2011-07-07 Revised:2011-09-15 Published:2011-10-09
  • Supported by:

    Project was supported by the National Natural Foundation of China (No. 20407002), the National Basic Research Program (973 program, No. 2002CB410802) and the Special Funds for State Key Joint Laboratory of Environmental Simulation and Pollution Control.

报道了在半波脉冲直流电(h-DC)作为电压驱动下, 以阳极氧化法制备的TiO2 纳米管(TNT)为工作电极, 紫外光光电催化(PEC)还原Cr(VI)的研究. 半波脉冲直流电相比稳压直流电(DC)和交流电(AC)具有更佳的载流子分离和光电催化作用. 探讨了电压大小、频率及电解质NaCl 浓度对Cr(VI)催化还原反应的影响. TNT光电催化和电催化还原Cr(VI) 效率随外加电压和频率的增大而增大, 但是频率过高对反应有一定的抑制作用. 电解质NaCl 对反应的影响不显著, 这是因为在重金属还原体系中, NaCl 作为活性氯物种的母体和增强溶液导电性的作用体现得不明显.

关键词: TiO2 纳米管, Cr(VI), 半波脉冲直流电, 交流电, 光电催化还原

In this paper, the photoelectrocatalytic (PEC) reduction of Cr(VI) over anodized TiO2 nanotube arrays under UV-light irradiation using the half-wave pulsed direct current (h-DC) as the applied voltage was reported. This mode of voltage brings about better separation of photogenerated electrons and holes, resulting in much higher photoelectrocatalytic efficiency than either the conventional direct current (DC) or the alternate current (AC). Under the half-wave pulsed direct current, the influence factors such as the value and frequency of the voltage, also concentration of the electrolyte (NaCl), on the PEC reduction of Cr(VI) were investigated. The PEC reduction rate increased with increasing voltage and frequency, but could be restrained by a high frequency. The concentration of NaCl exhibited little effect on the PEC reduction reaction of Cr(VI), for the weak function of active chlorine species and electric conduction in the heavy metal reduction system.

Key words: TiO2 nanotubes, Cr(VI), half-wave pulsed direct current, alternate current, photoelectrocatalytic reduction