Donor-Acceptor Oligothiophenes as Low Optical Gap Chromophores for Photovoltaic Applications

Extended donor-acceptor oligothiophenes exhibit a narrow optical energy gap in combination with strong light absorption and good intermolecular pi-pi stacking in the solid state for efficient charge transport. Bilayer photovoltaic devices utilizing these oligomers as p-type semiconducting photosensitizers afford high power conversion efficiencies of up to 2.7%.