High-Performance Non-Fullerene Organic Solar Cells Based on a Pair of Medium Band Gap Polymer Donor and Perylene Bisimide Derivative Acceptor

Herein, high performance solution-processed non-fullerene organic solar cells employing a medium band gap conjugated polymer (PBDTTS-TTffBT) and a bay-linked perylene bisimide derivative (di-PBI) as an electron donor and acceptor, respectively, have been demonstrated. Owing to the complementary absorption range and well-matched energy levels, PBDTTS-TTffBT and di-PBI have great potential for constructing high-performance non-fullerene organic solar cells. The facile control of blend film morphology by careful choice of a processing solvent achieves a promising power conversion efficiency of the device up to 6.51% with high open-circuit voltage (0.92 V), short circuit current density (10.89 mA cm(-2)), and a fill factor (0.65). Furthermore, the blend film exhibits high thermal stability, retaining >80% of its initial efficiency at 100 degrees C up to 120 min. This work demonstrates that the medium band gap is a promising candidate as a donor material for constructing high-performance non-fullerene organic solar cells.