Interfacial Engineering of Two-Dimensional Perovskite Memristors toward Reliable and Flexible Optoelectronic Memory Arrays.

Two-dimensional (2D) Ruddlesden-Popper halide perovskites are promising candidates for flexible optoelectronic memories owing to their tunable composition, reduced power consumption, and intrinsic structural anisotropy. Yet, achieving long-term reliability and environmental stability in perovskite-based memristors remains a major challenge. Here, we demonstrate highly oriented (PEA)2MA4Pb5I16 thin films integrated into optoelectronic memristors, where interface optimization with softly deposited Ag nanoparticles (NPs) enhances device performance without damaging the active layer. The resulting forming-free ITO/Ag NPs/(PEA)2MA4Pb5I16/Pt NPs/ITO devices exhibited robust binary resistive switching, with a large memory window (∼105), excellent endurance (>1011 cycles), and a low SET voltage (∼0.2 V). The confined conducting filament (CF) formation, induced by the vertically aligned crystalline domains, combined with the energetically favorable atom extraction from Ag NPs, ensured stable and low power switching under both electrical and optical stimuli. Numerical simulations were further conducted, elucidating the origin of the enhanced switching behavior and the role of crystal orientation in mitigating perovskite degradation pathways. The device conductance can be also modulated by applying light pulses, yielding a low energy consumption (∼100 nJ per programming event at 740 nm), whereas multicolor perception was achieved using additional wavelengths (450 and 550 nm). A 10 × 10 flexible crossbar array was fabricated, demonstrating high device yield, reproducible performance under bending, and excellent environmental stability over an extended period. This work establishes (PEA)2MA4Pb5I16 as a benchmark material for reliable, low-power, and optically programmable memristors and provides a scalable strategy for next-generation perovskite-based optoelectronic architectures.