Robust and Transient Write-Once-Read-Many-Times Memory Device Based on Hybrid Perovskite Film with Novel Room Temperature Molten Salt Solvent

Organic–inorganic hybrid perovskites (OIHPs) have emerged as a novel class of functional materials with applications in solar cells, photodetectors, light-emitting diodes, and resistive switching memories. Generally, perovskite films are fabricated with toxic solvents and antisolvent technique under inert atmosphere, which limits the commercial applications of OIHP-based devices. To address this issue, uniform CH₃NH₃PbBr₃ (MAPbBr₃) film is fabricated through a facile one-step spin-coating method by directly dissolving perovskite precursor in a room-temperature molten salt methylammonium acetate under air ambient condition. The nonvolatile resistive switching devices based on MAPbBr₃ exhibit robust and reproducible write-once-read-many-times (WORM) memory properties with a large ON/OFF ratio (10⁶), reliable retention properties (10⁴ s), and somewhat ternary resistive characteristic. The conductive filaments in the perovskite thin film are proposed to induce the electrical conductivity switching. Additionally, the MAPbBr₃ films can be dissolved rapidly in deionized water within 5 s, showing the transient characteristics. This work demonstrates a new perspective on the perovskite film fabrication and shows the potential application of MAPbBr₃ in transient WORM devices.