A donor-acceptor-donor (D-A-D) molecule based on 3-alkoxy-4-cyanothiophene and dithienopyrrole units as active material for organic solar cells

A symmetrical donor-acceptor-donor D-A-D system built by connecting two dithienopyrrole donor blocks to a central electron acceptor obtained by dimerization of 3-alkoxy-4-cyano-thiophene has been synthesized and characterized. The compound combines a high photoluminescence efficiency with a broad absorption spectrum in the solid state and a band gap of 1.70 eV. A preliminary evaluation of the potentialities of this type of compound as donor material in bulk heterojunction solar cells using PC 61 BM as electron acceptor is presented. The title compound has been synthesized and evaluated as donor material in bulk heterojunction organic solar cells.