Enhancement of Stability and Durability in Nanocrystal Memristors with Surface Defect Control for Image Encryption and Storage

Memristors based on perovskite materials demonstrate significant potential for applications in information encryption and storage. However, the stability and durability of their device structures remain major challenges for commercial deployment. In this study, Mn:CsPbCl 3 perovskite nanocrystals capped with short-chain ligands are synthesized at a controlled ratio using an in situ ligand passivation strategy. Compared with long-chain ligands, short-chain ligands possess higher surface adsorption energy, which enhances nanocrystal size uniformity and enables more effective attachment to the perovskite surface at adsorption sites. This process mitigates surface defects in the nanocrystals, thereby decreasing the randomness in conductive filaments formation and enhancing device stability. Furthermore, short-chain ligand capping improves the contact at the material-electrode interface correspondingly reducing leakage current. The fabricated short-chain Al/Mn:CsPbCl 3 /FTO memristor exhibits good reconfigurable storage behavior. By adjusting the compliance current, a transition from non-volatile to volatile storage modes is successfully achieved. Leveraging the device's electrical characteristics, binary image encryption, and storage functions are realized. Overall, this work demonstrates the importance of surface defects on the operational stability of nanocrystal memristors and provides a foundation for the application of perovskite memristors in information encryption and secure transmission.