Ultrasensitive and Robust 120 keV Hard X-Ray Imaging Detector based on Mixed-Halide Perovskite CsPbBr_{3- n} I_n Single...

The relatively low resistivity and severe ion migration in CsPbBr₃ significantly degrade the performance of X-ray detectors due to their high detection limit and current drift. The electrical properties and X-ray detection performances of CsPbBr₃ -nIn single crystals are investigated by doping the iodine atoms into the melt-grown CsPbBr₃ . The resistivity of CsPbBr₃ -nIn single crystals increases from 3.6 × 10⁹ (CsPbBr₃ ) to 2.2 × 10¹¹ (CsPbBr₂ I) Ω cm, restraining the leak current and decreasing the detection limit of the detector. Additionally, CsPbBr₃ -nIn single crystals exhibit stable dark currents, arising from their high ion migration activation energy. A record sensitivity of 6.3 × 104 µC Gy^-1 cm^-2 (CsPbBr_2.9 I_0.1 ) and a low detection limit of 54 nGy s^-1 (CsPbBr₂ I) are achieved by CsPbBr₃ -nIn single crystals for the 120 keV hard X-ray detection under a 5000 V cm^-1 electrical field. The CsPbBr_2.9 I_0.1 detector shows a stable current response with a dark current density of 0.58 µA cm^-2 for 30 days and clear imaging for 120 keV Xrays at ambient conditions. The effective iodine atom doping strategy makes the CsPbBr₃ -nIn single crystals promising for reproducible high-energy hard X-ray imaging systems.