Photocarrier dynamics in anatase TiO{sub 2} investigated by pump-probe absorption spectroscopy
- Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561 (Japan)
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8562 (Japan)
- Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)
The dynamics of photogenerated electrons and holes in undoped anatase TiO{sub 2} were studied by femtosecond absorption spectroscopy from the visible to mid-infrared region (0.1–2.0 eV). The transient absorption spectra exhibited clear metallic responses, which were well reproduced by a simple Drude model. No mid-gap absorptions originating from photocarrier localization were observed. The reduced optical mass of the photocarriers obtained from the Drude-model analysis is comparable to theoretically expected one. These results demonstrate that both photogenerated holes and electrons act as mobile carriers in anatase TiO{sub 2}. We also discuss scattering and recombination dynamics of photogenerated electrons and holes on the basis of the time dependence of absorption changes.
- OSTI ID:
- 22278116
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Band structure engineering of anatase TiO{sub 2} by metal-assisted P-O coupling
Visible Light Absorption and Hot Carrier Trapping in Anatase TiO2: The Role of Surface Oxygen Vacancies