Tailoring Cathode Interfaces for High-Performance Perovskite Solar Cells Using Perylene Diimide Derivatives with Ionic Diversity

Addressing the global demand for clean energy, perovskite solar cells (PVSCs) have emerged as one of the promising candidates. However, ensuring the stability of PVSCs under various environmental factors remains a critical issue for commercialization. Various ionic functionalities are incorporated into perylene diimide (PDIN) derivatives for altering the work function of aluminum electrodes. Well-known amino N-oxide terminal (PDIN-O), and quaternary ammonium salts (PDIN-Br and PDIN-I) were applied as cathode interlayer (CIL) materials in inverted PVSCs. Within the PDIN derivatives, PDIN-I stands out for its superior electron injection effectiveness, minimized energy losses, and enhanced interface contacts, resulting in an optimal device efficiency of 15.9%. The research emphasizes the role of efficient interlayer engineering in enhancing layer contact and coverage, inhibiting moisture permeation, and improving device stability. PDIN derivatives emerge as eco-friendly alternatives, offering promising prospects for stable and high-performance inverted PVSCs.