Vertically optimized phase separation with improved exciton diffusion enables efficient organic solar cells with thick active layers

Abstract The development of organic solar cells (OSCs) with thick active layers is of crucial importance for the roll-to-roll printing of large-area solar panels. Unfortunately, increasing the active layer thickness usually results in a significant reduction in efficiency. Herein, we fabricated efficient thick-film OSCs with an active layer consisting of one polymer donor and two non-fullerene acceptors. The two acceptors were found to possess enlarged exciton diffusion length in the mixed phase, which is beneficial to exciton generation and dissociation. Additionally, layer by layer approach was employed to optimize the vertical phase separation. Benefiting from the synergetic effects of enlarged exciton…

• NR
  National Research Foundation

  Awards: 2019R1A2C2085290, 2020M3H4A3081814
• NN
  National Natural Science Foundation of China

  Awards: 51825301, 21734001, 52003013, 51873172