Solution‐Processed Lead‐Free Perovskite Nanocrystal Scintillators for High‐Resolution X‐Ray CT Imaging

• Published in: Advanced optical materials 2021-06, Vol.9 (11), p.n/a
• Main Authors: Zhou, Jiaer, An, Kang, He, Peng, Yang, Jie, Zhou, Chang, Luo, Yi, Kang, Wei, Hu, Wei, Feng, Peng, Zhou, Miao, Tang, Xiaosheng
• Format: Article
• Language: English
• Subjects: Computed tomography; computed tomography imaging; Cs 3Cu 2I 5; Heavy metals; Image reconstruction; Lead compounds; lead‐free perovskites; low‐cost solution method; Materials science; Medical imaging; Metal halides; Nanocrystals; Optical fibers; Optics; Perovskites; Photoluminescence; Physical properties; Radiography; Scintillation counters; X‐ray detection
• ISSN: 2195-1071; 2195-1071
• DOI: 10.1002/adom.202002144

The physical properties of scintillators determine X‐ray detection performance directly, which plays a vital role in computed tomography (CT) imaging for medical radiography and security checks. Recently, lead halide perovskite materials have shown higher photoluminescence quantum yield (PLQY) than conventional X‐ray scintillators, but there are still some limitations, including instability and the use of heavy metal lead. In this study, a low‐temperature solution method is used to prepare 0D lead‐free Cs3Cu2I5 perovskite nanocrystals (NCs), and a corresponding optical fiber panel with Cs3Cu2I5 NCs is fabricated for high‐resolution X‐ray CT imaging. The Cs3Cu2I5 NCs exhibit a high PLQY of 59% and outstanding stability for more than three months. Importantly, the Cs3Cu2I5 NCs show a high radioluminescence (RL) light yield, that is four times higher than that of CsPbBr3 NCs (80 kV, 70 µA). In addition, an X‐ray detector based on a Cs3Cu2I5 NC scintillator is designed. Using this system, a clear projection image of a chip is obtained, and a 3D CT image of a snail is reconstructed. Therefore, the use of lead‐free perovskite nanocrystal scintillators is a promising technique for commercial X‐ray detection. A low‐temperature solution method is designed to prepare 0D Cs3Cu2I5 perovskite nanocrystals for economic purposes. The as‐prepared Cs3Cu2I5 exhibits strong luminescence properties under X‐ray irradiation. Using the Cs3Cu2I5‐based X‐ray imaging equipment, a clear projection image of a chip is obtained, and a 3D computed tomography image of a snail is reconstructed.