Probing Energy‐Funneling Kinetics in Nanocrystal Sublattices for Superior X‐Ray Imaging

• Published in: Angewandte Chemie International Edition 2024-06, Vol.63 (25), p.e202404177-n/a
• Main Authors: Wu, Qinxia, Xu, Xinqi, Li, Xiaokun, Jiang, Hao, Qin, Xian, Hong, Zhongzhu, Chen, Xiaofeng, Yang, Zhijian, Ou, Xiangyu, Xie, Lili, He, Yu, Han, Sanyang, Chen, Qiushui, Yang, Huanghao
• Format: Article
• Language: English
• Subjects: Controlled release; Density; Electronic traps; Electrons; Energy; Energy funneling; Gadolinium; Imaging; Kinetics; Microenvironments; Nanocrystal scintillators; Nanocrystals; Optical memory (data storage); Radioluminescence afterglow; Scintillation counters; X-ray imaging
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202404177

Long‐lasting radioluminescence scintillators have recently attracted substantial attention from both research and industrial communities, primarily due to their distinctive capabilities of converting and storing X‐ray energy. However, determination of energy‐conversion kinetics in these nanocrystals remains unexplored. Here we present a strategy to probe and unveil energy‐funneling kinetics in NaLuF4:Mn2+/Gd3+ nanocrystal sublattices through Gd3+‐driven microenvironment engineering and Mn2+‐mediated radioluminescence profiling. Our photophysical studies reveal effective control of energy‐funneling kinetics and demonstrate the tunability of electron trap depth ranging from 0.66 to 0.96 eV, with the corresponding trap density varying between 2.38×105 and 1.34×107 cm−3. This enables controlled release of captured electrons over durations spanning from seconds to 30 days. It allows tailorable emission wavelength within the range of 520–580 nm and fine‐tuning of thermally‐stimulated temperature between 313–403 K. We further utilize these scintillators to fabricate high‐density, large‐area scintillation screens that exhibit a 6‐fold improvement in X‐ray sensitivity, 22 lp/mm high‐resolution X‐ray imaging, and a 30‐day‐long optical memory. This enables high‐contrast imaging of injured mice through fast thermally‐stimulated radioluminescence readout. These findings offer new insights into the correlation of radioluminescence dynamics with energy‐funneling kinetics, thereby contributing to the advancement of high‐energy nanophotonic applications. Energy‐funneling kinetics in NaLuF4: Mn2+/Gd3+ nanocrystals were explored through precise microenvironment engineering within nanocrystal sublattices. The resulting tailorable radioluminescence afterglow enabled high‐sensitivity, high‐resolution X‐ray imaging with an ultralong optical memory.