Enhanced Electronic Quality of Perovskite via a Novel C60 o-Quinodimethane Bisadducts toward Efficient and Stable Perovskite Solar Cells

As one of the more promising potential photovoltaic technologies, planar perovskite solar cells (PSCs) are arousing worldwide interest for their many advantages. Now, PSCs are being developed toward the direction of high-performance and longevity. However, the defects of the polycrystalline perovskite active layer limit further improvement of the device performance. Seeking simple and efficient strategies to reduce these trap states in the perovskite active layer is highly desirable. Here, a novel nonfunctionalized fullerene C60 o-quinodimethane bisadduct [C60(QM)2] was dissolved in chlorobenzene (CB) solvent and introduced into a CH3NH3PbI3 active layer by antisolvent dripping. Results showed that the introduced C60(QM)2 could effectively reduce the trap density of the MAPbI3 active layer, facilitating carrier extraction/injection from CH3NH3PbI3 to spiro-OMeTAD. As a result, a highest PCE of 18.4% for the PSC based on CH3NH3PbI3/C60(QM)2 was obtained, which increased by 10.1% compared with 16.7% for the...