Photoelectrochemical spectroscopy studies of titanium dioxide surfaces: theory and experiment
| Autor: | Nacir Tit, Marek T. Michalewicz, William H. Smyrl, M. R. Kozlowski, J. W. Halley |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Chemical substance
Chemistry technology industry and agriculture Mineralogy chemistry.chemical_element Surfaces and Interfaces Electronic structure Condensed Matter Physics Oxygen Surfaces Coatings and Films chemistry.chemical_compound Chemical physics Rutile Titanium dioxide Materials Chemistry Direct and indirect band gaps Spectroscopy Science technology and society |
| Zdroj: | Surface Science. 256:397-408 |
| ISSN: | 0039-6028 |
| DOI: | 10.1016/0039-6028(91)90882-s |
| Popis: | We describe experimental and theoretical studies of titanium dioxide. Photoelectrochemical data are presented for surfaces of known structure. The oxides were grown anodically on titanium metal. We report calculations of the electronic densities of states and optical conductivities of rutile TiO 2 in finite-size samples disordered by the addition of oxygen vacancies for comparison with experiments. We conclude that in less disordered surfaces the electronic structure exhibited by the photospectra is very close to that of bulk rutile TiO 2 . In contrast, very thin oxides showed evidence of an electronic structure dominated by localized states near the band edge. More disordered oxides gave photospectra in which transitions associated with direct band gap transitions in bulk TiO 2 seem to have been suppressed. Taking the structural information on the oxides into account, we argue that this suppression is probably a matrix element effect. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|