Organic scintillators, pivotal in security and medical applications, face challenges due to limited X‐ray absorption and exciton utilization. Herein, a novel class of organic scintillators is introduced, named guest‐induced thermally activated delayed fluorescence (TADF) within supramolecular macrocycles via host‐guest through‐space charge transfer (TSCT). Four co‐crystals are obtained through orthogonal crystallizations involving calix[3]acridan (C[3]A) and calix[3]phenothiazine (C[3]P) macrocycles as hosts, along with 1,2‐dicyanobenzene (DCB) and 4‐bromo‐1,2‐benzenedicarbonitrile (BrDCB) as guests. Interestingly, DCB@C[3]A and BrDCB@C[3]A co‐crystals exhibit strong host‐guest TSCT with reduced single‐triplet energy gap for efficient TADF emission, which leads to enhanced exciton utilization and X‐ray absorption, yielding radioluminescence intensities over 29 and 25 times higher than C[3]A. Similarly, substituting C[3]A with C[3]P, the obtained TADF co‐crystals also outperform C[3]P in scintillation performance. Additionally, the scintillation color of co‐crystals can be adjusted by varying the electron‐donating abilities of macrocycles and the electron‐accepting abilities of guests, offering a simpler color‐tuning mechanism than covalent‐bonded scintillators. Furthermore, the flexible film based on DCB@C[3]A exhibits promising application in X‐ray radiography, showcasing a high spatial resolution of 20 lp mm−1 @MTF = 0.77. The innovative strategy of fabricating organic scintillators via reversible non‐covalent interactions presents a novel solution for designing color‐tunable and high‐performance scintillators.

中文翻译：

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用于高分辨率 X 射线成像的客体诱导热激活延迟荧光有机超分子大环闪烁体

有机闪烁体在安全和医疗应用中至关重要，但由于 X 射线吸收和激子利用率有限而面临挑战。在此，引入了一类新型有机闪烁体，称为超分子大环内通过主客体空间电荷转移（TSCT）的客体诱导热激活延迟荧光（TADF）。通过正交结晶获得四种共晶，涉及杯[3]吖啶丹（C[3]A）和杯[3]吩噻嗪（C[3]P）大环作为主体，以及1,2-二氰基苯（DCB）和4-溴-1,2-苯二甲腈（BrDCB）作为客体。有趣的是，DCB@C[3]A和BrDCB@C[3]A共晶表现出强的主客体TSCT，减少了单三重态能隙，从而实现高效的TADF发射，从而提高了激子利用率和X射线吸收，产生的放射发光强度比 C[3]A 高 29 倍和 25 倍。同样，用C[3]P替代C[3]A，所得TADF共晶的闪烁性能也优于C[3]P。此外，共晶的闪烁颜色可以通过改变大环化合物的给电子能力和客体的电子接受能力来调节，提供比共价键闪烁体更简单的颜色调节机制。此外，基于DCB@C[3]A的柔性薄膜在X射线照相中展现出广阔的应用前景，表现出20 lp mm的高空间分辨率−1@MTF = 0.77。通过可逆非共价相互作用制造有机闪烁体的创新策略为设计颜色可调的高性能闪烁体提供了一种新颖的解决方案。