Pyrroloindacenodithiophene containing polymers for organic field effect transistors and organic photovoltaicsElectronic supplementary information (ESI) available. See DOI: 10.1039/c1jm13428k

The synthesis of the novel electron-rich pyrroloindacenodithiophene (NIDT) unit is reported. Stille copolymerization of the distannylated NIDT unit, with the electron-deficient dibrominated benzothiadiazole (BT), difluorobenzothiadiazole (ffBT), thienopyrrolodione (TPD) and 1,1′-bithienopyrrolodione (biTPD) units afforded a series of low band gap semiconducting polymers. Initial testing shows promise for the use of these materials as p-type semiconductors in organic field effect transistors (OFETs) with mobilities as high as 0.07 cm 2 V −1 s −1 being measured. These materials have also been tested as the donor polymer in polymer/fullerene bulk heterojunction organic photovoltaics (OPVs) giving maximum efficiencies of 2.5%. Four copolymers synthesized with a novel unit, pyrroloindacenoditiophene, were tested in OFET (μ max 0.07 cmV −1 s −1 ) and OPV (η max 2.5%) devices.