Hydrogen Evolution from Water by Visible Light, a Homogeneous Three Component Test System for Redox Catalysis

Abstract

Abstract Irradiation by visible light of a neutral aqueous solution containing Ru (bipy) as a sensitizer, methylviologen (MV +2 ) as an electron acceptor and triethanolamine or cysteine as an electron donor leads to the formation of stable methylviologen radical cation (MV + ). The kinetics and mechanism of the photoinduced reactions occurring in such a system were explored by laser photolysis technique. In the presence of Adams catalyst MV + is reoxidized by water under simultaneous evolution of hydrogen. Optimum conditions for the water reduction under continuous illumination are elaborated and implications for an energy conversion system discussed.