X‐Ray Irradiation Fluence‐Dependent Carrier Transport Capacity of MAPbBr₃ Single Crystal

Abstract Significant progress is achieved in the development of hybrid lead halide perovskite‐based X‐ray detectors. An in‐depth understanding of the impact of X‐ray irradiation on charge carrier behaviors is essential to assess the long‐term operational reliability of these devices. In this study, high‐quality methylammonium lead bromide (MAPbBr₃) single crystals with good environmental stability are grown by an inverse temperature method, and the evolution of their carrier transport capacity is investigated by tracking the optoelectronic properties of MAPbBr₃ single crystal devices under X‐ray irradiation with different fluence. Notably, the carrier transport capacity is enhanced when the X‐ray fluence is between 1.2 × 10¹⁷ and 1.8 × 10¹⁷ photons, as evidenced by improved optoelectronic properties and reduced trap state density. Conversely, a larger X‐ray fluence of 3.6 × 10¹⁷ photons causes unrepaired decomposition of the MAPbBr₃ single crystals and severe degradation of their carrier transport capacity. These findings provide valuable insights for the application of hybrid lead perovskite single crystals in X‐ray detection, emphasizing the importance of optimizing X‐ray fluence levels for sustained device performance.