Benzo[d]thiazole Based Wide Bandgap Donor Polymers Enable 19.54% Efficiency Organic Solar Cells Along with Desirable Batch‐to‐Batch Reproducibility and General Applicability

The limited selection pool of high-performance wide bandgap (WBG) polymer donors is a bottleneck problem of the nonfullerene acceptor (NFA) based organic solar cells (OSCs) that impedes the further improvement of their photovoltaic performances. Herein, a series of new WBG polymers, namely PH-BTz, PS-BTz, PF-BTz, and PCl-BTz, are developed by using the bicyclic difluoro-benzo[d]thiazole (BTz) as the acceptor block and benzo[1,2-b:4,5-b']dithiophene (BDT) derivatives as the donor units. By introducing S, F, and Cl atoms to the alkylthienyl sidechains on BDT, the resulting polymers exhibit lowered energy levels and enhanced aggregation properties. The fluorinated PBTz-F not only exhibits a low-lying HOMO level,…

• UD
  U.S. Department of Energy

  Awards: No. DE-SC0012704, SC0012704
• NN
  National Natural Science Foundation of China

  Awards: 21905185, DE-SC0012704, 22075190, 21825502, 22105135
• SU
  Sichuan University

  Awards: 2020CDZG-6, 2020CDYB-28
• FR
  Fundamental Research Funds for the Central Universities

  Awards: YJ202116, YJ202069, YJ201957, DE-SC0012704
• BN
  Brookhaven National Laboratory

  Awards: SC0012704, No. DE-SC0012704, Contract No. DE-SC0012704