From Static to Dynamic: Rethinking Interface Passivation in Inverted Perovskite Solar Cells

Interface passivation is central to efficiency improvement in inverted perovskite solar cells, yet its effectiveness is fundamentally limited by the assumption of a static picture. Herein, we argue that the perovskite/electron transport layer interface is intrinsically dynamic under operation, continuously evolving under illumination, thermal stress, and electrical bias owing to ion migration, interfacial redistribution, passivator destabilization, and chemical reactions. These coupled processes progressively reconstruct interfacial energetics and defect landscapes, leading to voltage loss, fill-factor decay, hysteresis re-emergence, and irreversible performance degradation even in devices with high initial efficiencies. By reframing the interface as a time-dependent system rather than a fixed structure, this perspective highlights dynamic interfacial evolution as the origin of long-term instability and calls for interface regulation strategies that prioritize sustained functional stability under realistic operating conditions.