Pyrene-fused PDI based ternary solar cells: high power conversion efficiency over 10%, and improved device thermal stability

Abstract

Although great advances have been achieved in the field of organic solar cells (OSCs) with the rapid development of nonfullerene acceptors (NFAs), devices with simultaneous high power conversion efficiency (PCE) and thermal stability remain a big challenge, particular small molecule NFA-based devices. In this paper, we designed and synthesized a class of pyrene-fused perylene diimides (PDIs) for fabricating ternary OSCs, which exhibited much better device performance than those of the parent PDI counterpart based devices due to the better miscibility and crystallization of the ternary films. Excitingly, Th-PYPDI and O-PYPDI based ternary OSCs showed improved thermal stability, as a result of the better morphology stability under the same annealing conditions. Notably, the O-PYPDI based ternary device exhibited the best PCE of 10.96% and good thermal stability with the PCE remaining at 82% of the initial value after thermal annealing at 80 °C for 72 h.