Suppression of Surface Recombination on TiO2 Anatase Photocatalysts in Aqueous Solutions Containing Alcohol

作者：Oleg A. Semenikhin, Vladimir E. Kazarinov, Lei Jiang, Kazuhito Hashimoto, Akira Fujishima · 发表于：Langmuir · 年份：1999 · DOI：10.1021/la981437b · 被引用次数：37 · 研究领域：TiO2 Photocatalysis and Solar Cells、Advanced Photocatalysis Techniques、Water Quality Monitoring and Analysis

Intensity-modulated photocurrent spectroscopy (IMPS) was applied to studying the mechanism of photoelectrochemical decomposition of a model organic compound, ethanol, on a TiO 2 anatase photoelectrode in aqueous solution. The frequency spectra of the intensity-modulated photocurrents observed on the TiO 2 photoelectrode at low band bending were drastically changed in the presence of alcohol. Without the alcohol, the frequency dependence of the modulated photocurrents were similar to those reported previously for TiO 2 electrodes and were typical for the case of surface recombination occurring on surface states, while upon addition of alcohol the photocurrent frequency dependence was no longer observed. This fact suggests that alcohol suppresses the recombination processes at the surface of the TiO 2 photoelectrode. Possible mechanisms for this phenomenon are discussed. The results demonstrate that IMPS is a powerful tool for studying the mechanism of photocatalytic decomposition of organic pollutants on semiconductor electrodes.