2005年7月
Time-resolved infrared absorption study of photochemical reactions over metal oxides
TOPICS IN CATALYSIS
- ,
- ,
- ,
- 巻
- 35
- 号
- 3-4
- 開始ページ
- 211
- 終了ページ
- 216
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1007/s11244-005-3826-0
- 出版者・発行元
- SPRINGER/PLENUM PUBLISHERS
The present account describes how photochemical reactions over metal oxides are traced by time-resolved infrared (IR) absorption spectroscopy. The ac-coupled amplification of the IR signal allows detection of transient absorbance changes as small as 10(-6) with a time resolution of 50 ns. Band-gap excited electrons in TiO2 and NaTaO3 present a structureless absorption of IR light from 3000 to 1000 cm(-1). Reaction-perturbed decay of this absorption evidences the assignment to photoexcited electrons, not to holes. The efficiency of the water splitting reaction on NaTaO3-based catalysts correlates with the quantity of electrons detected by the IR absorption. A short-lived intermediate state of 2-propanol oxidation on TiO2 is identified by its vibrational band at 1640 cm(-1) superposed on the structureless absorption of electrons. Ru dye (N3) on a TiO2 film is irradiated with a 532-nm light pulse to simulate dye-sensitized solar cells. The neutralization rate of dye cations and the decay rate of electrons injected in the film are quantified, leading to a three-state model which describes the relaxation of injected electrons. These results demonstrate the ability of this method in tracing photochemical kinetics over metal oxides.
- リンク情報
- ID情報
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- DOI : 10.1007/s11244-005-3826-0
- ISSN : 1022-5528
- J-Global ID : 200902299537593269
- Web of Science ID : WOS:000232264900003