PHOTOINDUCED HYDROGEN EVOLUTION USING WATER-SOLUBLE VIOLOGEN-LINKED TRISULFONATOPHENYLPORPHYRINS (TPPSCNV) WITH HYDROGENASE

A series of water soluble viologen-linked trisulfonatophenylporphyrins with different methylene chain lengths (n = 3-6) between porphyrin an d viologen, TPPSCnV, were synthesized and were characterized. The intr amolecular electron transfer rate constants from the porphyrin moiety of TPPSCnV to viologen were measured by using fluorescence lifetime an d laser flash photolysis. The photoexcited singlet state of the porphy rin was quenched by the bonded viologen. These compounds were applied to photoinduced hydro en evolution in the system containing nicotinami de-adenine dinucleotide phosphate a(reduced form NADPH), TPPSCnV and h ydrogenase under steady stare irradiation. (C) 1997 Elsevier Science B .V.