Electron Transfer Mediators for Photoelectrochemical Cells Based on Cu(I) Metal Complexes

The preparation and the photoelectrochemical characterization of a series of bipyridine and pyridyl-quinoline Cu(I) complexes, used as electron transfer mediators in regenerative photoelectrochemical cells, are reported. The best performing mediators produced maximum IPCEs of the order of 35–40%. The J-V curves recorded under monochromatic light showed that the selected Cu(I)/(II) couples generated higher Vocs and fill factors compared to an equivalentI-/I3-cell, due to a decreased dark current.