Visible light, cyclic water cleavage

Cyclic water cleavage by visible light was also achieved in electron relay free systems (48). In this case the fraction of sensitizer that Is absorbed onto the particle surface is photoactive and electron injection occurs directly from its excited state into the Ti02 conduction band. Using the surfactant ruthenium complex depicted in Figure 10, a quantum yield of 7% was obtained for the water splitting process. 

Figure 9. Cyclic water cleavage by visible light in the presence of Ru(bipy)i as a sensitizer and bifunctional redox catalyst as an electron relay.

The study of heterogeneous photosystems, involving u.v. or visible light irradiation of aqueous suspensions of semiconductor powders or colloids, has increased steadily over the past five years. Many studies are aimed at development of systems capable of cyclic water cleavage, although, as mentioned earlier, Ti02 doped with iron functions as a photocatalyst for reduction of N2 to The most popular semiconductor materials continue to be TiOj... 

Cyclic Water Cleavage Induced by Visible Light with Coupled Redox Catalysts. 101... 

Kiwi J, Borgarello E, Pellizzetti E, Visca M, Gratzel M (1980) Cyclic water cleavage by visible light drastic improvement of yield of H2 and O2 with bifunctional redox catalysts. Angew Chem Int Ed 19 646-648... 

Kalayanasundaram K, Gratzel M (1979) Cyclic cleavage of water into H2 and O2 by visible light with coupled redox catalysts. Angew Chem Int Ed 18 701-702... 

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