High-performance polymer heterojunction solar cells of a polysilafluorene derivative

High-performance polymer heterojunction solar cells fabricated from an alternating copolymer of 2,7-silafluorene (SiF) and 4,7-di(2(')-thienyl)-2,1,3-benzothiadiazole (DBT) (PSiF-DBT) as the electron donor blended with [6,6]-phenyl-C-61-butyric acid methyl ester as the electron acceptor were investigated. A power-conversion efficiency up to 5.4% with an open-circuit voltage of 0.90 V, a short-circuit current of 9.5 mA cm(-2), and a fill factor of 50.7% was achieved under the illumination of AM 1.5 G from a calibrated solar simulator (800 W m(-2)). The field-effect transistors fabricated from PSiF-DBT showed a high hole mobility of similar to 1x10(-3) cm(2) V-1 s(-1). (C) 2008 American Institute of Physics.