Low band gap benzothiophene–thienothiophene copolymers with conjugated alkylthiothieyl and alkoxycarbonyl cyanovinyl side chains for photovoltaic applications
Alkylthiothieyl substituted benzothiophene (BDT) and alkoxycarbonyl cyanovinyl modified thienothiophene (TT) were copolymerized to obtain a new low band gap copolymer PBDTTT-S-CN with a efficiency of 7.00%.