Incorporating MXene in Perovskite for Modulating Ion Migration and Enhancing Object Detection

Perovskite memristors hold promise for next-generation computing devices due to their potential for in-memory computing. However, they face challenges in practical applications owing to high power consumption, limited resistance tunability, and complex conduction mechanisms primarily caused by the uncontrollable ion migrations. In this study, Ti₃C₂T_x MXene nanosheets are incorporated into the methylammonium lead iodide (MAPbI₃) based memristor to modulate the migration behaviors of iodine (I⁻) and silver (Ag⁺) ions. Ti₃C₂T_x can decrease the Ag⁺ ions migration barrier from 0.45 to 0.31 eV, which is induced by the closer lattice distance and lower charge transfer barrier thanks to the bridging effect between Pb²⁺ and the surface functional groups of MXene. Thus, lower operating voltages can be achieved. On the other hand, MXene can also serve as a “reservoir” for the accumulation of I⁻ ions, leading to gradual ion migration and stable multiple resistive states under repeated voltage stimulations. Herein, Ag⁺ and I⁻ ions migration processes are considered to dominate the digital and analog switching behaviors of the device, respectively, enabling the applications in both data storage and neuromorphic computing with long retention time (>10⁵ s), high device uniformity, multiple distinguishable resistance states (21 states), and high object detection accuracy (98.9%).