Ambipolar-transport wide-bandgap perovskite interlayer for organic photovoltaics with over 18% efficiency

•There is effective Förster resonance energy transfer from MAPbBr3 to PM6 •18.3% is among the highest efficiency for OPVs without thermal annealing of active layers •MAPbBr3 can effectively transport electrons in OPVs as long as the energy level aligns Anode interface layers (AILs) are of vital importance to the performance of organic photovoltaics (OPVs). Herein, MAPbBr3 is firstly demonstrated as an effective solution-processed AIL, featuring a 2.3-eV bandgap and high hole and electron mobility. PM6:BO-4Cl based on unannealed device with the MAPbBr3 AIL exhibits an encouraging efficiency of 15.5%. F4TCNQ is further doped into MAPbBr3 to increase work function and passivate defects, boosting the efficiency to 17.3%. Likewise, the unannealed devices based on PM6:BTP-eC9:PC71BM achieved a high efficiency of 18.3% with the MAPbBr3/F4TCNQ AIL. The ambipolar ability of MAPbBr3 in OPVs was further proved by inverted devices. Therefore, MAPbBr3 successfully serves multiple functions: a down-conversion layer, an energy donor, and a textured seeding layer influencing bulk-heterojunction (BHJ) morphology. This finding successfully demonstrates the practicability of wide-bandgap perovskite materials as highly promising OPV interfacial materials. Anode interface layers (AILs) are of vital importance to the performance of organic photovoltaics (OPVs). Herein, MAPbBr3 is firstly demonstrated as an effective solution-processed AIL, featuring a 2.3-eV bandgap and high hole and electron mobility. PM6:BO-4Cl based on unannealed device with the MAPbBr3 AIL exhibits an encouraging efficiency of 15.5%. F4TCNQ is further doped into MAPbBr3 to increase work function and passivate defects, boosting the efficiency to 17.3%. Likewise, the unannealed devices based on PM6:BTP-eC9:PC71BM achieved a high efficiency of 18.3% with the MAPbBr3/F4TCNQ AIL. The ambipolar ability of MAPbBr3 in OPVs was further proved by inverted devices. Therefore, MAPbBr3 successfully serves multiple functions: a down-conversion layer, an energy donor, and a textured seeding layer influencing bulk-heterojunction (BHJ) morphology. This finding successfully demonstrates the practicability of wide-bandgap perovskite materials as highly promising OPV interfacial materials.