Self‐Powered Ferroelectric Bi‐Based Perovskite X‐Ray Detector for Radiation Monitoring and Intelligent Imaging Recognition

Abstract The advancement of 0D Bi‐based perovskites for X‐ray detection is limited by the difficulty of exciton dissociation and charge transport within isolated 0D structures, resulting in relatively low sensitivity, especially under 0 V bias. Herein, a lead‐free ferroelectric perovskite (Br‐PA) 3 BiI 3 Br 3 has been developed with a large saturation polarization (0.39 µC cm −2 ). The spontaneous ferroelectric polarization facilitates carrier separation and transport, resulting in a reduced exciton binding energy (112.8 meV) and an extended carrier lifetime (0.96 ms), ultimately leading to a substantial mobility‐lifetime product (1.08 × 10 −3 cm 2 V −1 ). Thus, the X‐ray detector based on (Br‐PA) 3 BiI 3 Br 3 achieves a sensitivity of up to 743 µC Gy air −1 cm −2 at 0 V bias, which is among the highest reported for self‐powered lead‐free perovskite X‐ray detectors. Furthermore, the inherent 0D structure significantly increases the activation energy for ion migration (808.9 meV), leading to a low current drift of 7.63 × 10 −17 A cm −1 V −1 s −1 and significantly improved operational stability. Based on self‐powered characteristics, a portable X‐ray monitoring system is successfully demonstrated to provide real‐time monitoring and feedback to a mobile user interface. Furthermore, an image processing algorithm and a back propagation neural network are used for image recognition, improving accuracy by 20% and significantly reducing the energy consumption.