Mechanistic studies of the one-electron oxidation of water to hydroxyl radicals photosensitized by perfluorinated p-terphenyl

Abstract

Photo-oxidation of water in a system consisting of perfluorinated p-terphenyl (F-OPP-3) as a photosensitizer, O₂ as an oxidative quencher and benzene as a hydroxyl radical scavenger is mechanistically studied by laser flash photolysis and γ-ray and pulse radiolysis. The radical cation of F-OPP-3 (F-OPP-3˙⁺) is formed via the oxidative quenching of its excited singlet state by O₂. The decay of F-OPP-3˙⁺ observed in transient spectroscopy is enhanced by the addition of water to the system, indicating that F-OPP-3˙⁺ plays a crucial role in the one-electron oxidation of water.