In particular, various X-ray applications with different energies result in different requirements for the detector. For instance, both X-ray diffraction (XRD) and X-ray fluorescence mainly need to detect X-rays with energies lower than 10 keV in scientific research. In contrast, X-rays with energy of 25-50 keV are used to produce images in mammography and chest radiography, [4] while computed tomography (CT) is equipped with digital X-ray image detectors with energy of 80-150 keV. [5,6] Current semiconductor materials such as Si, α-Se, HgI 2 , PbI 2 , and CdZnTe (CZT) are widely applied in direct detectors but suffer from some drawbacks. [7][8][9] Si and α-Se detectors have small attenuation coefficients for light atoms that limit the detection of X-rays to less than 50 keV. HgI 2 and PbI 2 detectors have large leakage currents and poor stability. A commercial CZT detector, which has excellent energy resolution and good photopeak efficiency, is expensive for single crystal (SC) growth and suffers from defects related to charge trapping. [10] Therefore, it is necessary to explore new materials for high-performance radiation detection.In recent years, metal halide perovskites have attracted increasing attention for room-temperature nuclear radiation detection due to their high atomic number (Cs,55, Pb, 82, Br, 35 and I,53), tunable band gap (E g = 1.56-3 eV), [11,12] high resistivity (R = 10 7 -10 12 Ω cm), [13,14] large mobility lifetime product (μτ = 10 −5 to 10 −2 cm 2 V −1 ), [15,16] and low cost in SC growth. These advantageous properties result in large ray attenuation and increased carrier collection efficiency (CCE) for both perovskite SCs and polycrystalline thin films. However, despite their high sensitivity of ≈10 6 -10 8 µC Gy −1 cm −2 , which is two to seven orders of magnitude higher than that of α-Se (20 µC Gy −1 cm −2 ) and CZT (12 000 µC Gy −1 cm −2 ), [17,18] and extremely low detection limit of 0.61 nGy s −1 , which is four orders of magnitude smaller than regular medical diagnostic requirement of 5.5 εGy s −1 , [19] previous studies conducted using these materials have mainly focused on the detection of soft X-rays with energy of several to tens of keV. [18,[20][21][22][23] Few studies have been performed on detecting hard X-rays, specifically in the range greater than 100 keV, which is required in CT imaging and positron emission tomography. In fact, the penetration depthsThe relatively low resistivity and severe ion migration in CsPbBr 3 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 CsPbBr 3 −nIn single crystals are investigated by doping the iodine atoms into the melt-grown CsPbBr 3 . The resistivity of CsPbBr 3 −nIn single crystals increases from 3.6 × 10 9 (CsPbBr 3 ) to 2.2 × 10 11 (CsPbBr 2 I) Ω cm, restraining the leak current and decreasing the detection limit of the detector. Additionally, CsPbBr 3 −nIn single crystals exhibit stable dark currents, arising fro...
