Efficient Integrated Perovskite/Organic Solar Cells via Interdigitated Interfacial Charge Transfer

The architecture of integrated perovskite/organic solar cells (IPOSCs) is a promising strategy to further enhance the power conversion efficiency (PCE) by extending their photoresponse to the near-infrared range. To maximize the potential benefits of the system, it is crucial to optimize the perovskite crystallinity and intimate morphology of the organic bulk heterojunction (BHJ). More importantly, efficient charge transfer between the interface of the perovskite and BHJ plays a key role in the success of IPOSCs. This paper reports efficient IPOSCs by forming interdigitated interfaces between the perovskite and BHJ layers. Large microscale perovskite grains enable the infiltration of BHJ materials into the perovskite grain boundary, thereby increasing the interface area and promoting efficient charge transfer. Owing to the synergetic effect of the interdigitated interfaces and optimized BHJ nanomorphology, the developed P-I-N-type IPOSC exhibited an excellent PCE of 18.43% with a J_sc of 24.44 mA/cm², a V_oc of 0.95 V, and a FF of 79.49%, which is one of very efficient hybrid perovskite-polymer solar cells.