Photo-oxidation of water in non-sacrificial systems

Abstract

The irradiation of bipy₃Ru²⁺ in acidic aqueous solution containing iron(III) and colloidal RuO₂·2H₂O, resulting in formation of O₂ with a quantum efficiency of ca. 48%, has been studied. At pH 1.9, the rate of O₂ formation was 2.6 × 10^–6 mol dm^–3 min ^–1 and the total yield of O₂ obtained upon prolonged irradiation was 9.1 × 10^–4 mol dm^–3. With mercury(II) as electron acceptor, O₂ formation was less efficient but it could be observed at pH 3.