Synchronous Regulation of Charge Transfer and Defects in Perovskite Nanocomposite Films for Enhanced Sensitivity and Stability in Monolithically Integrated X‐Ray Imaging Arrays

Abstract Perovskites nanocrystals (PNCs) have garnered significant research interest in X‐ray detection due to their strong X‐ray absorption capability, and unique advantages in large area and thick film deposition that result from the decoupling of perovskite crystallization from film formation. However, traditional long‐chain ligands used in PNCs, such as oleic acid and oleyl amine, suffer from poor conductivity and susceptibility to detachment, which limits the performance of X‐ray detectors based on them. In this study, a strategy is proposed to partially replace long‐chain ligands with short‐chain counterparts like phenethylammoniumbromide (PEABr) and CF ₃ PEABr, during the synthesis of CsPbBr ₃ PNCs. This approach leads to a lower defect density, enhanced carrier transport, and suppressed ion migration simultaneously in the resulting PNCs. These PNCs are then combined with organic bulk heterojunction to construct the nanocomposite X‐ray detectors, which exhibit an impressive sensitivity of 10787 µC Gy _air ⁻¹ cm⁻ ² and stable dark current baseline under a large electric field of ≈17 000 V cm ⁻¹ . Finally, a flat panel X‐ray imaging sensor is prepared by monolithically integrating the nanocomposite film with a thin‐film transistor backplane, enabling high‐resolution and real‐time X‐ray imaging. The image quality is further enhanced through a super‐resolution reconstruction approach, effectively facilitating a wide range of practical applications in real‐world scenarios.