Journal of Molecular Catalysis A-Chemical, Vol.151, No.1-2, 7-15, 2000
Photoinduced hydrogen evolution with bisviologen-linked ruthenium(II) complexes and hydrogenase
Bisviologen-linked ruthenium(II) complexes with different methylene chain length between ruthenium complex and viologen, Ru(bpy)(2)(dcbpy)CmVACnVB(m = 2, n = 3, m = 3, n = 4), were synthesized and characterized. From luminescence spectra, the photoexcited state of Ru(bpy),(dcbpy) moiety is oxidatively quenched by the bound viologen, and an intramolecular electron transfer occurs. Luminescence lifetime measurements show that the electron transfers from the photoexcited state of ruthenium(II) complex moiety to the bound bisviologen more rapidly than that of monoviologen-linked ruthenium(II) complexes. Ru(bpy)(2)(dcbpy)CmVACnVB were applied to the photoinduced hydrogen evolution in the system containing nicotinamide-adenine dinucleotide phosphate (reduced form, NADPH), Ru(bpy)(2)(dcbpy)CmVACnVB and hydrogenase under steady state irradiation. In the case of Ru(bpy)(2)(dcbpy)C3VAC4VB, the efficient photoinduced hydrogen evolution was observed.
Keywords:photoinduced hydrogen evolution;bisviologen-linked ruthenium(II) complexes hydrogenase;intramolecular electron transfer