Coupling of a Copper Dye with a Copper Electrolyte: A Fascinating Springboard for Sustainable Dye-Sensitized Solar Cells

A simple new heteroleptic copper dye, bearing one 2,9-dimesityl-1,10-phenanthroline and a 6,6′-dimethyl-2,2′-bipyridine-4,4′-dibenzoic acid anchoring ligand, was used as photosensitizer in dye-sensitized solar cells (DSSCs). High power conversion efficiencies are reached not only with conventional I–/I3 – electrolyte (40% relative conversion efficiency respect to N719) but, remarkably, also with a well-designed copper-based electrolyte. These proof-of-principle “full-copper” DSSCs open a fascinating route for environmentally friendly DSSCs.