• benzothiadiazole;
  • conjugated polymer photovoltaic materials;
  • donor-acceptor copolymers;
  • dithienosilole;
  • polymer solar cells


A donor-acceptor (D-A) copolymer, PDTSDOBT, based on dithienosilole and 5,6-bis(octyloxy)benzo[1,2,5]thiadiazole is synthesized by Pd-catalyzed Stille coupling reaction for application as a donor material in polymer solar cells (PSCs). The polymer shows good thermal stability, strong absorption in the visible region, and a relatively low bandgap of 1.63 eV. The hole mobility of PDTSDOBT as measured by SCLC is 5.58 × 10−4 cm2 V−1 s−1. The power conversion efficiency of a PSC based on PDTSDOBT: PC70BM (1:2 w/w) is 3.51% with a short-circuit current density of 8.96 mA cm−2, an open-circuit voltage of 0.69 V, and a fill factor of 0.568, under the 100 mW cm−2 AM1.5G illumination.