Ultrahigh‐Flux X‐ray Detection by a Solution‐Grown Perovskite CsPbBr₃ Single‐Crystal Semiconductor Detector

Abstract

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 3 single-crystal semiconductor detector capable of operating at ultrahigh X-ray flux of 10 10 photons s −1 mm −2 is reported. High-quality solution-grown CsPbBr 3 single crystals are fabricated into detectors with a Schottky diode structure of eutectic gallium indium/CsPbBr 3 /Au. A high reverse-bias voltage of 1000 V (435 V mm −1 ) can be applied with a small and stable dark current of ≈60-70 nA (≈9-10 nA mm −2 ), which enables a high sensitivity larger than 10 000 μC Gy air −1 cm −2 and a simultaneous low detection limit of 22 nGy air s −1 .The CsPbBr 3 semiconductor detector shows an excellent photocurrent linearity and reproducibility under 58.61 keV synchrotron X-rays with flux from 10 6 to 10 10 photons s −1 mm −2 . 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 3 single crystal may be associated with its good short-range order, comparable to the spectrometer-grade melt-grown CsPbBr 3 .

One-Dimensional CsCu2I3 Single-Crystal X-ray Detectors

“…Over the past few years, three-dimensional (3D) halide perovskites have attracted intensive attention for X-ray detection, owing to their excellent absorption coefficients, high carrier mobility, long carrier diffusion length, high defect tolerance, and tunable band gaps. − For example, Tang et al provided X-ray detectors based on intrinsic CsPbBr 3 , which achieved a low detection limit of 103.6 nGy air s –1 . Kanatzidis et al reported CsPbBr 3 -based X-ray detectors with a low detection limit of 22 nGy air s –1 . Besides, MAPbI 3 has also been used for X-ray detection with a detection limit of 340 nGy air s –1 .…”

Ultrasensitive and Robust CsPbBr3 Single-Crystal X-ray Detectors Based on Interface Engineering

“…Due to the outstanding bias stability, an excellent sensitivity of 7.3 × 10 4 μC Gy air s −1 cm −2 is achieved for the Au/Al/BCP/C 60 / CsPbBr 3 /Au device at 100 V (Figure 5d), which is one of the highest sensitivities achieved by detectors based on CsPbBr 3 SCs. 48,49 The corresponding on−off responses to fit the sensitivity curves are shown in Figure S7. However, for Au/Al/ CsPbBr 3 /Au, the sensitivity is limited for the instability caused by a severe electrochemical reaction (Figures S8 and S9).…”

Suppressed Ion Migration for High-performance X-ray Detectors Based on Atmosphere-Controlled EFG-Grown CsPbBr3 Single Crystals

“…3 A high sensitivity and a low detection limit are two important parameters for X-ray detectors to acquire a high image resolution while minimizing damage to the human body. 11 The highest reported sensitivity of 2.2 ×10 8 µC Gy air −1 cm − 2 for 8 keV X-ray photons has been achieved in MAPbI 3 lms, which is 6-7 orders of magnitude larger than that for α-Se (20 µC Gy air −1 cm − 2 ). 12 Generally, such high sensitivities were attained with several hundred micrometre perovskite lms in the detection of soft X-rays below 50 keV with a strong photoconductive gain effect in the thin lms.…”

“…Furthermore, low trap concentrations are essential for SC X-ray detectors to obtain a high CCE, which provides high sensitivity while maintaining a low detection limit. 11 Among all perovskites, the all-inorganic halide perovskite CsPbBr 3 SC has attracted considerable attention for its great structural and thermal stability compared to organic-inorganic hybrid perovskites.…”