Co-sensitization promoted light harvesting for plastic dye-sensitized solar cells

Abstract

A stepwise co-sensitization of a TiO2 mesoporous film in conjunction with two dye molecules, using different sequences of adsorption for achieving a complementary spectral characteristic, is investigated for application to a low-temperature fabrication plastic dye-sensitized solar cell (plastic DSSCs). The stepwise co-sensitization by monomolecular adsorption of N719/FL and black dye/FL show enhanced photovoltaic performances for the pertinent plastic DSSCs, compare with that of the cell with the corresponding individual dyes. The optimal conversion efficiencies of plastic DSSCs with N719/FL and black dye/FL are found to be 5.10% and 3.78%, respectively, which are higher than those of the cells with the corresponding individual sensitizers. The incident photon-to-current conversion efficiency (IPCE) and electrochemical impedance spectroscopy (EIS) are also used to analysis these behaviors. © 2010 Elsevier B.V.