Suppression of surface recombination on TiO{sub 2} anatase photocatalysts in aqueous solutions containing alcohol

Journal Article · Tue May 25 04:00:00 EDT 1999 · Langmuir

DOI:https://doi.org/10.1021/la981437b· OSTI ID:352687

Semenikhin, O A; Kazarinov, V E ^[1]; Jiang, L ^[2]; Hashimoto, K ^[2]; Fujishima, A ^[3]

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1. Russian Academy of Sciences, Moscow (Russian Federation). A.N. Frumkin Inst. of Electrochemistry
2. Chinese Academy of Sciences, Beijing (China). Inst. of Chemistry
3. Univ. of Tokyo (Japan)

Intensity-modulated photocurrent spectroscopy (IMPS) was applied to studying the mechanism of photoelectrochemical decomposition of a model organic compound, ethanol, on a TiO{sub 2} anatase photoelectrode in aqueous solution. The frequency spectra of the intensity-modulated photocurrents observed on the TiO{sub 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{sub 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{sub 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.

• OSTI ID: 352687
• Journal Information: Langmuir, Journal Name: Langmuir Journal Issue: 11 Vol. 15; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
40 CHEMISTRY
CATALYTIC EFFECTS
ETHANOL
PHOTOCURRENTS
PHOTOLYSIS
RECOMBINATION
TITANIUM OXIDES
WASTE WATER
WATER TREATMENT