Donor–acceptor conjugated polymers based on thieno[3,2-b]indole (TI) and 2,1,3-benzothiadiazole (BT) for high efficiency polymer solar cells

Three conjugated polymers based on the thieno[3,2-b]indole (TI) unit as electron-donor block and benzothiadiazole (BT) as electron-accepting block and thiophene rings as spacers. Their photovoltaic performance were finely tuned by thiophene spacers.