Terpolymerization strategy to achieve high-efficiency organic solar cells via construction of D1–A–D1–D2-type polymer donors.

Novel terpolymers were developed with ester group incorporation (BDT-2EST). DM1 with 5% BDT-2EST possesses suitable crystallinity and miscibility matching with Y6 acceptor to offer an excellent power conversation efficiency up to 17.21%. Moreover, the intertwined random features in DM1 offer robust photovoltaic performances with a broad molecular weight tolerance. [ABSTRACT FROM AUTHOR]