Boosting the efficiency of organic solar cells via dual non-fullerene acceptors

To prepare high-performance organic solar cells (OSCs), incorporating a third component into the binary blend is a feasible and convenient strategy. Here, IDIC, a non-fullerene small molecule acceptor with medium bandgap and good compatibility, was added to the PM6:BTP-eC9 system to prepare high-performance ternary OSCs. The good absorption, compatibility and energy level of IDIC can contribute to enhance light-harvesting, obtain better nanofiber structures, promote the exciton dissociation and charge transport, and suppress recombination. Finally, the optimized ternary OSCs achieves a high power conversion efficiency (PCE) up to 18.53%, which is higher than that of the binary system (17.09%). Additionally, IDIC was also used as a third component to build efficient OSCs in other binary systems and achieved enhanced photovoltaic performance. This work proves that selecting a third component having appropriate absorption and good compatibility to fabricate high-performance ternary OSCs is an effective and convenient strategy.