Low Ghosting Perovskite X‐Ray Imager

Abstract Perovskite detectors hold promise for application in next‐generation X‐ray imaging. Among these, many dynamic imaging application scenarios have high requirements for low ghosting. However, current 3D perovskite materials are affected by ion migration, exhibiting noticeable ghosting, which impacts the reliability and accuracy of detection. Here, quasi‐2D perovskite thick film detectors are fabricated by preferentially selecting shorter A‐site diamine cations N, N‐dimethyl‐1, 3‐propylenediamine hydroiodate (DMePDA 2+ ) and optimizing the layers of the lead‐iodide framework. These detectors exhibit lower ion migration while maintaining charge carrier mobility comparable to 3D perovskites. X‐ray imaging results demonstrate that detectors fabricated from these materials exhibit only 1.6% ghosting, significantly outperforming 3D perovskites (7.5%). The work provides new insights and approaches to reduce ghosting in perovskite flat‐panel detectors, which is of great significance for promoting progress in the entire field of perovskite optoelectronic devices.