The dramatic improvement of the PCE (power conversion efficiency) of organic photovoltaic devices in the past few years has been driven by the development of new polymer donor materials and non-fullerene acceptors (NFAs). In the design of such materials synthetic scalability is often not considered, and hence complicated synthetic protocols are typical for high-performing materials. Here we report an approach to readily introduce a variety of solubilizing groups into a benzo[c][1,2,5]thiadiazole acceptor comonomer. This allowed for the ready preparation of a library of eleven donor polymers of varying side chains and comonomers, which facilitated a rapid screening of properties and photovoltaic device performance. Donor FO6-T emerged as the optimal material, exhibiting good solubility in chlorinated and non-chlorinated solvents and achieving 15.4% PCE with L8BO as the acceptor (15.2% with Y6) and good device stability. FO6-T was readily prepared on the gram scale, and synthetic complexity (SC) analysis highlighted FO6-T as an attractive donor polymer for potential large scale applications.
Bibliographical noteKAUST Repository Item: Exported on 2023-08-31
Acknowledged KAUST grant number(s): OSR-2020-CRG8-4095
Acknowledgements: We would like to thank the Engineering and Physics Science Research Council (EPSRC) (EP/V048686/1, EP/R513052/1 and EP/T028513/1), the Royal Society and Wolfson Foundation, and the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. OSR-2020-CRG8-4095 for the financial support. This work was performed in part on the SAXS/WAXS beamline72 at the Australian Synchrotron, part of ANSTO. YK and CL appreciate financial support from the National Research Foundation (NRF) of Korea (2021R1I1A3A04037494).