A theoretical investigation on photocatalytic oxidation on the TiO{sub 2} surface
Abstract
The TiO{sub 2} photocatalytic oxidation mechanism was theoretically investigated by using long-range corrected time-dependent density functional theory (LC-TDDFT) with a cluster model of the anatase TiO{sub 2}(001) surface. We found that LC-TDDFT with the cluster model quantitatively reproduces the photoexcitations of the TiO{sub 2} surface by calculating the electronic spectra of a clean TiO{sub 2} surface and one with oxygen defects. We calculated the electronic spectra of a molecularly adsorbed TiO{sub 2} surface for the adsorptions of phenol, methanol, and methane molecules as typical organic molecules. We obtained the surprising result that the main peak of the phenol-adsorbed TiO{sub 2} surface, which overlaps with the main peak of the clean TiO{sub 2} surface, corresponds to charge transfers from the phenol molecule to the TiO{sub 2} surface. This indicates that the TiO{sub 2} photocatalytic oxidation proceeds through direct charge transfer excitation from the substrate molecules to the TiO{sub 2} surface. In contrast, we found slight and no charge transfer for methanol and methane adsorption, respectively, in agreement with the experimental findings for their reactivities. In light of these results, we propose a new mechanism for heterogeneous TiO{sub 2} photocatalytic oxidations.
- Authors:
-
- Department of Applied Chemistry, School of Engineering, University of Tokyo, Tokyo 113-8656 (Japan)
- Advanced Science Institute, RIKEN, Wako, Saitama 351-0198 (Japan)
- Publication Date:
- OSTI Identifier:
- 22047156
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Chemical Physics
- Additional Journal Information:
- Journal Volume: 136; Journal Issue: 2; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ADSORPTION; CLUSTER MODEL; DENSITY FUNCTIONAL METHOD; METHANE; METHANOL; MOLECULES; OXIDATION; OXYGEN; PHENOL; PHOTOCATALYSIS; PHOTOCHEMISTRY; REACTION KINETICS; SEMICONDUCTOR MATERIALS; SURFACES; TITANIUM OXIDES
Citation Formats
Suzuki, Satoshi, Tsuneda, Takao, Hirao, Kimihiko, and CREST, Japan Science and Technology Agency. A theoretical investigation on photocatalytic oxidation on the TiO{sub 2} surface. United States: N. p., 2012.
Web. doi:10.1063/1.3676261.
Suzuki, Satoshi, Tsuneda, Takao, Hirao, Kimihiko, & CREST, Japan Science and Technology Agency. A theoretical investigation on photocatalytic oxidation on the TiO{sub 2} surface. United States. https://doi.org/10.1063/1.3676261
Suzuki, Satoshi, Tsuneda, Takao, Hirao, Kimihiko, and CREST, Japan Science and Technology Agency. 2012.
"A theoretical investigation on photocatalytic oxidation on the TiO{sub 2} surface". United States. https://doi.org/10.1063/1.3676261.
@article{osti_22047156,
title = {A theoretical investigation on photocatalytic oxidation on the TiO{sub 2} surface},
author = {Suzuki, Satoshi and Tsuneda, Takao and Hirao, Kimihiko and CREST, Japan Science and Technology Agency},
abstractNote = {The TiO{sub 2} photocatalytic oxidation mechanism was theoretically investigated by using long-range corrected time-dependent density functional theory (LC-TDDFT) with a cluster model of the anatase TiO{sub 2}(001) surface. We found that LC-TDDFT with the cluster model quantitatively reproduces the photoexcitations of the TiO{sub 2} surface by calculating the electronic spectra of a clean TiO{sub 2} surface and one with oxygen defects. We calculated the electronic spectra of a molecularly adsorbed TiO{sub 2} surface for the adsorptions of phenol, methanol, and methane molecules as typical organic molecules. We obtained the surprising result that the main peak of the phenol-adsorbed TiO{sub 2} surface, which overlaps with the main peak of the clean TiO{sub 2} surface, corresponds to charge transfers from the phenol molecule to the TiO{sub 2} surface. This indicates that the TiO{sub 2} photocatalytic oxidation proceeds through direct charge transfer excitation from the substrate molecules to the TiO{sub 2} surface. In contrast, we found slight and no charge transfer for methanol and methane adsorption, respectively, in agreement with the experimental findings for their reactivities. In light of these results, we propose a new mechanism for heterogeneous TiO{sub 2} photocatalytic oxidations.},
doi = {10.1063/1.3676261},
url = {https://www.osti.gov/biblio/22047156},
journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 2,
volume = 136,
place = {United States},
year = {Sat Jan 14 00:00:00 EST 2012},
month = {Sat Jan 14 00:00:00 EST 2012}
}