物理化学学报 >> 2009, Vol. 25 >> Issue (12): 2427-2432.doi: 10.3866/PKU.WHXB20091210

研究论文 上一篇    下一篇

含氟水溶液中电化学刻蚀氟化WO3薄膜电极增强可见光光电化学性能

李文, 冷文华, 牛振江, 李想, 费会, 张鉴清, 曹楚南   

  1. 浙江大学玉泉校区化学系, 杭州 310027; 浙江师范大学物理化学研究所, 浙江 金华 321004; 中国科学院金属研究所, 金属腐蚀与防护国家重点实验室, 沈阳 110016
  • 收稿日期:2009-05-17 修回日期:2009-08-23 发布日期:2009-11-27
  • 通讯作者: 冷文华 E-mail:lengwh@zju.edu.cn

Enhanced Photoelectrochemical Performance of WO3 Film Electrode under Visible Light by Electrochemical Etching Fluorination in Aqueous Solutions Containing Fluorine

LI Wen, LENG Wen-Hua, NIU Zhen-Jiang, LI Xiang, FEI Hui, ZHANG Jian-Qing, CAO Chu-Nan   

  1. Department of Chemistry, Yuquan Campus, Zhejiang University, Hangzhou 310027, P. R. China; Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, Zhejiang Province, P. R. China; State Key Laboratory for Corrosion and Protection of Metals, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, P. R. China
  • Received:2009-05-17 Revised:2009-08-23 Published:2009-11-27
  • Contact: LENG Wen-Hua E-mail:lengwh@zju.edu.cn

摘要:

报道了在含氟的酸性水溶液中, 对电沉积制备的WO3薄膜电极进行电化学刻蚀, 并采用光电化学、扫描电子显微镜(SEM)、X射线衍射(XRD)、光电子能谱(XPS)、紫外-可见漫反射光谱、光致发光(PL)等方法对电极进行了表征. 结果表明, 刻蚀使电极比表面积增大, 质量减少, 重要的是可使电极表面状态发生变化. 在相同催化剂质量和比表面积的条件下, 这种变化显著提高了WO3薄膜电极在可见光和紫外-可见光照下的光电转换性能. 机理研究表明, 电极光电化学性能提高可归因于刻蚀使电极表面发生氟化, 光生载流子表面复合中心数目减少, 平带电位负移. 刻蚀对电极的吸光性质和晶体结构等未检测出明显变化. 氟化电极在酸性中具有良好的光电化学稳定性.

关键词: WO3, 电化学刻蚀, 氟化, 光电化学, 可见光

Abstract:

A new and simple method of electrochemical etching in acidic aqueous solutions containing fluorine for the electrodeposited WO3 thin films is presented. The samples were characterized by photoelectrochemistry, scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy, and photoluminescence (PL). Results showed that the etching increased the specific surface area with a concomitant reduction in the catalyst mass and also a change in the surface status of the electrodes. This modification of the surface status improved the photoelectrochemical performance of the electrodes under visible and UV-Vis light illumination with the same mass and specific surface area. This enhancement can be ascribed to the surface fluorination of the electrodes, which result in a decrease in the surface recombination centers and a negative shift in the flatband potential. The light absorption and crystalline were found to be unchanged by etching. The etched WO3 film electrode shows excellent photoelectrochemical stability in acid solutions. This provides a novel method for increasing the photon electric conversion efficiency of WO3 thin filmelectrodes.

Key words: WO3, Electrochemical etching, Fluorination, Photoelectrochemistry, Visible light

MSC2000: 

  • O646