A Redox-Based Resistive Switching Memory Device Consisting of Organic–Inorganic Hybrid Perovskite/Polymer Composite Thin Film

This study describes the first perovskite-based redox resistive switching memory using CH₃NH₃PbBr₃ nanoparticles (NPs) dispersed in an insulating solid polymer electrolyte, poly(ethylene oxide) (PEO), and scrutinizes it in detail. Herein, PEO is chosen not only to perform a matrix function due to its ionic conductivity but also to support a preservative material surrounding the CH₃NH₃PbBr₃ NPs to improve their stability. Further, it is revealed that PEO can serve as the chelating agent to coordinate with PbBr₂/CH₃NH₃PbBr₃ NPs in consequence of the direct interaction between Pb²⁺ cations and electron pairs of ether oxygen on the PEO chain to provide a host medium for the Pb²⁺ cations on both amorphous and crystalline phases. Consequently, it facilitates the associated redox-based reactions to result in the metallic filament formation in the derived device, leading to the write-once-read-many times resistive switching behavior. The field-effect scanning electron microscopy and X-ray photoelectron spectroscopy analyses are conducted to ascertain the detailed mechanism. It is unveiled that a stable dendritic-like filament is grown in the CH₃NH₃PbBr₃ NPs:PEO hybrid film, which is thus proposed to be the origin of the stable low resistive state and recovery of the conductive path during the reverse bias scan. This study presents a new perspective on the perovskite-based resistive memory devices.