Lattice engineering for stabilized black FAPbI<sub>3</sub> perovskite single crystals for high-resolution x-ray imaging at the lowest dose.

Chu, Depeng; Jia, Binxia; Liu, Naiming; Zhang, Yunxia; Li, Xiaotong; Feng, Jiangshan; Pi, Jiacheng; Yang, Zhou et al. · Sci Adv · 2023

basic_science · Level V

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Abstract

Preliminary theoretical analyses indicate that lattice relaxation may be used to release lattice strain in the FAPbI<sub>3</sub> perovskite to warrant both high x-ray detection performance and improved stability. Herein, we demonstrate stable black α-phase FAPbI<sub>3</sub> single crystals (SCs) realized by lattice engineering via annealing in the ambient atmosphere. The engineered α-FAPbI<sub>3</sub> SC detector shows almost all the best figures of merit including a high sensitivity of 4.15 × 10<sup>5</sup> μC Gy<sub>air</sub><sup>-1</sup> cm<sup>-2</sup>, a low detection limit of 1.1 nGy<sub>air</sub> s<sup>-1</sup>, a high resolution of 15.9 lp mm<sup>-1</sup>, and a short response time of 214 μs. We further demonstrate high-definition x-ray imaging at a dose rate below 10 nGy<sub>air</sub> s<sup>-1</sup> on the FAPbI<sub>3</sub> SC, indicating a minimal dose-area product of 0.048 mGy<sub>air</sub> cm<sup>2</sup> to the patient for one-time posteroanterior chest diagnosis, which is more than 3000 times lower than the international reference level of 150 mGy<sub>air</sub> cm<sup>2</sup>. In addition, the robust long-term stability enables the FAPbI<sub>3</sub> SC x-ray detector to work steadily for more than 40 years.