From “common” copper complexes to “smart” redox mediators in DSSCs: the role of electrochemistry

Production of electricity from the abundant and ubiquitous solar light could represent a real means to ensure a sustainable energy demands of humans, and dye-sensitized solar cells (DSSCs) can be one of the potential alternatives. In such a photoelectrochemical devices photon-to-electron conversion is possible exploiting a sensitized photoanode for light harvesting and a redox mediator for cycling of the device. Electron mediators represent surely an intriguing challenge for synthetic chemists but, first of all, for electrochemists. In fact a perfect knowledge of their electrochemical features are among the most important prerogatives to identify promising candidates alternative to the benchmark I3-/I- couple that it is far from being an ideal mediator. In this context I will show how electrochemistry could make the difference, transforming “common” copper complexes in “smart” components acting as efficient electron shuttles in DSSCs able to neatly outperform iodine-based electrolyte, also reaching interesting conversion efficiency > 6%.