Abstract

The dye-sensitized solar cell was first proposed by Grätzel and O'Regan in 1991. The idea behind this architecture was to use a dye to absorb visible light and then inject electrons into a wide bandgap semiconductor electrode, generating an electric current. The key component of the dye-sensitized solar cell was the dye molecule, inspired by the reaction center from natural photosynthesis in plants, which absorbs light and converts it into chemical energy. In recent years, this architecture has been adapted for synthesis where rather than generating a current, light-induced charge separation is used to transfer redox equivalents to a substrate initiating a chemical transformation. Devices driving these processes are known as dye-sensitized photoelectrochemical cells.
Previously, our group has shown that a copper(I)-based donor-chromophore-acceptor molecular system immobilized on a zinc oxide photoanode together with a copper(II)-based water oxidation catalyst can act as a light-harvesting photocatalytic assembly to split water. To enable the complementary reaction to reduce the protons formed from water splitting, we have designed a photocathode comprised of a copper(I)-based chromophore-acceptor dyad complex to drive a well-studied cobaloxime hydrogen evolving electrocatalyst with visible light. The molecular structures, optical properties and electrochemistry properties of the synthesized materials were characterized using techniques such as nuclear magnetic resonance spectroscopy, UV-Visible spectroscopy and cyclic voltammetry. In this thesis, the dye molecule dyad was installed on fluorine doped-tin oxide glass with a nickel oxide film and will work in concert with the previously studied photoanode to give a tandem cell where hydrogen gas as a solar fuel is expected to be produced effectively.