Electrophoretic Deposition of a Reduced Graphene-Au Nanoparticle Composite Film as Counter Electrode for CdS Quantum Dot-Sensitized Solar Cells

A reduced graphene (RG)-Au nanoparticle composite film is successfully fabricated by electrophoretic deposition and used as counter electrode for quantum dot-sensitized solar cells. The RG-Au composite is prepared by one-step microwave-assisted reduction of chloroaurate in alkaline solution with graphite oxide dispersion. Under one sun illumination (AM 1.5 G, 100 mW?cm-2), the cell with a RG-Au counter electrode shows an energy conversion efficiency of 1.36?%, which is higher than those of cells employing conventional Pt or Au counter electrodes, due to the superior combination of highly catalytic Au nanoparticles and the conductive graphene network structure.