Metal chalcogenide complex-mediated fabrication of Cu2S film as counter electrode in quantum dot sensitized solar cells

Cu₂S film onto FTO glass substrate was obtained to function as counter electrode for polysulfide redox reactions in CdS/CdSe co-sensitized solar cells by sintering after spraying a metal chalcogenide complex, N₄H₉Cu₇S₄ solution. Relative to Pt counter electrode, the Cu₂S counter electrode provides greater electrocatalytic activity and lower charge transfer resistance. The prepared Cu₂S counter electrode represented nanoflower-like porous film which was composed of Cu₂S nanosheets on FTO and had a higher surface area and lower sheet resistance than that of sulfided brass Cu₂S counter electrode. An energy conversion efficiency of 3.62% was achieved using the metal chalcogenide complex-mediated fabricated Cu₂S counter electrode for CdS/CdSe co-sensitized solar cells under 1 sun, AM 1.5 illumination.