Advanced Membranes and Porous Materials Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia.
KAUST Catalysis Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia.
Adv Sci (Weinh). 2023 Jul;10(19):e2300406. doi: 10.1002/advs.202300406. Epub 2023 Apr 21.
X-ray imaging technology is critical to numerous different walks of daily life, ranging from medical radiography and security screening all the way to high-energy physics. Although several organic chromophores are fabricated and tested as X-ray imaging scintillators, they generally show poor scintillation performance due to their weak X-ray absorption cross-section and inefficient exciton utilization efficiency. Here, a singlet fission-based high-performance organic X-ray imaging scintillator with near unity exciton utilization efficiency is presented. Interestingly, it is found that the X-ray sensitivity and imaging resolution of the singlet fission-based scintillator are dramatically improved by an efficient energy transfer from a thermally activated delayed fluorescence (TADF) sensitizer, in which both singlet and triplet excitons can be efficiently harnessed. The fabricated singlet fission-based scintillator exhibits a high X-ray imaging resolution of 27.5 line pairs per millimeter (lp mm ), which exceeds that of most commercial scintillators, demonstrating its high potential use in medical radiography and security inspection.
X 射线成像技术在日常生活的众多领域都至关重要，从医疗放射学和安全检查到高能物理学等领域都有应用。尽管已经有几种有机生色团被制造出来并测试为 X 射线成像闪烁体，但由于它们的 X 射线吸收截面较弱且激子利用效率不高，通常表现出较差的闪烁性能。在这里，提出了一种基于单线态裂变的高性能有机 X 射线成像闪烁体，其激子利用效率接近 1。有趣的是，研究发现，通过热激活延迟荧光（TADF）敏化剂的有效能量转移，可以显著提高基于单线态裂变的闪烁体的 X 射线灵敏度和成像分辨率，其中可以有效地利用单线态和三线态激子。所制备的基于单线态裂变的闪烁体表现出高的 X 射线成像分辨率为 27.5 线对每毫米（lp mm），超过了大多数商业闪烁体，表明其在医学放射学和安全检查中有很高的应用潜力。
