Photocurrent Generation from Water via PSII Membranes Immobilized on Dye-Derivatized TiO₂ Electrodes

Abstract

During photosynthesis light energy absorbed by the photosynthetic reaction centres is converted to chemical energy in the form of ATP and NAD(P)H₂: in photoelectrochemical cells light energy absorbed by a sensitized electrode is converted to electrical or chemical energy. For example, if a TiO₂ semiconductor electrode (anode) coated with a dye (to improve the visible light sensitivity of the electrode) is irradiated with visible light the dye molecules get excited and inject electrons into the conduction band of the TiO₂. These electrons can be directed towards a counter electrode (cathode) to generate a photocurrent — continuous photocurrent is produced in the presence of a reductant which would reduce the oxidised dye (1).