Mechanochemical synthesis of high-entropy perovskite toward highly sensitive and stable X-ray flat panel detector.

Perovskites are attracting attentions for optoelectronic devices. Despite its promise, the large-scale synthesis of perovskite materials with exact stoichiometry, especially high-entropy perovskites, has been a major challenge. Moreover, the difficulty in stoichiometry control also hinders the development of perovskite X-ray flat panel detectors. Previous reports all employed simple MAPbI 3 as the active layer, while the performance still falls short of optimized single crystal-based single pixel detectors. Herein we adopt the scalable and universal strategy of a mechanochemical method to synthesize stoichiometric high-entropy perovskite powders with high quality and high quantity (>1 kg per batch). By utilizing these stoichiometric perovskites, we report the first FA 0.9 MA 0.05 Cs 0.05 Pb(I 0.9 Br 0.1 ) 3 -based X-ray flat panel detectors with low trap density and large mobility-lifetime product (7.5×10 -3 cm 2 V -1 ). The assembled panel detector exhibits close-to-single-crystal performance (high sensitivity of 2.1×10 4 μC Gy air -1 cm -2 , ultralow detection limit of 1.25 nGy air s -1 ), high spatial resolution of 0.46 lp/pixel, as well as excellent thermal robustness under industrial standards. The high performance in in the high-entropy perovskite-based X-ray FPDs has the potential to facilitate the development of new-generation X-ray detection systems. This article is protected by copyright. All rights reserved.