Ultrasensitive and stable X-ray detection using zero-dimensional lead-free perovskites
Date
2020
Authors
Zheng, Xiaojia
Zhao, Wei
Wang, Peng
Tan, Hairen
Saidaminov, Makhsud I.
Tie, Shujie
Chen, Ligao
Peng, Yufei
Long, Jidong
Zhang, Wen-Hua
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of Energy Chemistry
Abstract
Sensitive and reliable X-ray detectors are essential for medical radiography, industrial inspection and security screening. Lowering the radiation dose allows reduced health risks and increased frequency and fidelity of diagnostic technologies for earlier detection of disease and its recurrence. Three-dimensional (3D) organic–inorganic hybrid lead halide perovskites are promising for direct X-ray detection – they show improved sensitivity compared to conventional X-ray detectors. However, their high and unstable dark current, caused by ion migration and high dark carrier concentration in the 3D hybrid perovskites, limits their performance and long-term operation stability. Here we report ultrasensitive, stable X-ray detectors made using zero-dimensional (0D) methylammonium bismuth iodide perovskite (MA3Bi2I9) single crystals. The 0D crystal structure leads to a high activation energy (Ea) for ion migration (0.46 eV) and is also accompanied by a low dark carrier concentration (~ 106 cm−3). The X-ray detectors exhibit sensitivity of 10,620 µC Gyair−1 cm−2, a limit of detection (LoD) of 0.62 nGyair s−1, and stable operation even under high applied biases; no deterioration in detection performance was observed following sensing of an integrated X-ray irradiation dose of ~23,800 mGyair, equivalent to > 200,000 times the dose required for a single commercial X-ray chest radiograph. Regulating the ion migration channels and decreasing the dark carrier concentration in perovskites provide routes for stable and ultrasensitive X-ray detectors.
Description
Keywords
X-ray detector, Zero-dimensional perovskite, Lead-free, Carrier concentration, Stability, Limit of detection, Sensitivity
Citation
Zheng, X., Zhao, W., Wang, P., Tan, H., Saidaminov, M. I., Tie, S., Chen, L., Peng, Y., Long, J., & Zhang, W. (2020). Ultrasensitive and stable X-ray detection using zero-dimensional lead-free perovskites. Journal of Energy Chemistry, Vol. 49, 299- 306. https://doi.org/10.1016/j.jechem.2020.02.049.