Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA.
Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA.
Adv Mater. 2023 Jun;35(25):e2211840. doi: 10.1002/adma.202211840. Epub 2023 Apr 29.
Solution-processed perovskites are promising for hard X-ray and gamma-ray detection, but there are limited reports on their performance under extremely intense X-rays. Here, a solution-grown all-inorganic perovskite CsPbBr single-crystal semiconductor detector capable of operating at ultrahigh X-ray flux of 10 photons s mm is reported. High-quality solution-grown CsPbBr single crystals are fabricated into detectors with a Schottky diode structure of eutectic gallium indium/CsPbBr /Au. A high reverse-bias voltage of 1000 V (435 V mm ) can be applied with a small and stable dark current of ≈60-70 nA (≈9-10 nA mm ), which enables a high sensitivity larger than 10 000 µC Gy cm and a simultaneous low detection limit of 22 nGy s . The CsPbBr semiconductor detector shows an excellent photocurrent linearity and reproducibility under 58.61 keV synchrotron X-rays with flux from 10 to 10 photons s mm . Defect characterization by thermally stimulated current spectroscopy shows a similar low defect density of a synchrotron X-ray and a lab X-ray irradiated device. Solid-state nuclear magnetic resonance spectroscopy suggests that the excellent performance of the solution-grown CsPbBr single crystal may be associated with its good short-range order, comparable to the spectrometer-grade melt-grown CsPbBr .
溶液处理的钙钛矿在硬 X 射线和伽马射线检测方面很有前景,但关于它们在极强 X 射线下的性能的报道有限。在这里,我们报道了一种能够在 10 个光子 s mm 的超高 X 射线通量下工作的溶液生长的全无机钙钛矿 CsPbBr 单晶半导体探测器。高质量的溶液生长 CsPbBr 单晶被制成具有共晶镓铟/ CsPbBr / Au 肖特基二极管结构的探测器。可以施加 1000 V 的高反向偏压(435 V mm ),并且暗电流稳定在 ≈60-70 nA(≈9-10 nA mm )左右,这使得灵敏度大于 10 000 µC Gy cm ,同时检测限低至 22 nGy s 。CsPbBr 半导体探测器在通量为 10 到 10 个光子 s mm 时,在 58.61 keV 的同步加速器 X 射线下表现出优异的光电流线性度和重现性。热刺激电流光谱学的缺陷特征表明,同步加速器 X 射线和实验室 X 射线辐照器件的缺陷密度相似。固态核磁共振波谱表明,溶液生长的 CsPbBr 单晶的优异性能可能与其良好的短程有序有关,与光谱级别的熔融生长的 CsPbBr 相当。