Direct Observation of Reactive Trapped Holes in TiO2 Undergoing Photocatalytic Oxidation of Adsorbed Alcohols:  Evaluation of the Reaction Rates and Yields

• Published in: Journal of the American Chemical Society Vol. 128; no. 2; pp. 416 - 417
• Main Authors: Tamaki, Yoshiaki, Furube, Akihiro, Murai, Miki, Hara, Kohjiro, Katoh, Ryuzi, Tachiya, M
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 18-01-2006
• Subjects: Charge carriers: generation, recombination, lifetime, and trapping; Chemistry; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; Electronic transport in condensed matter; Exact sciences and technology; General and physical chemistry; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Physics; Catalytic reaction; Transition metal Compounds; Charge carrier density; Photocatalysis; Photochemical reaction; Experimental study; Absorption spectrometry; Near ultraviolet radiation; Charge carrier recombination; Oxidative degradation; Alkanol; Kinetic parameter; Rate constant; Titanium oxide; Catalyst activity
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja055866p

To investigate the primary process of photocatalytic oxidation of TiO2, interfacial charge-transfer reaction of trapped holes formed in nanocrystalline TiO2 films by UV irradiation was directly measured by highly sensitive femtosecond and nanosecond transient absorption spectroscopy under low intensity excitation condition to avoid fast electron−hole recombination. Accordingly, the rates and yields of photocatalytic oxidation of several alcohols adsorbed on TiO2 were evaluated successfully.