Wu Haodi, Wang Qian, Zhang Ao, Niu Guangda, Nikl Martin, Ming Chen, Zhu Jinsong, Zhou Zhengyang, Sun Yi-Yang, Nan Guangjun, Ren Guohao, Wu Yuntao, Tang Jiang
Wuhan National Laboratory for Optoelectronics (WNLO) and School of Optical and Electronic Information, Huazhong University of Science and Technology (HUST), Wuhan 430074, China.
Artificial Crystal Research Center, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201899, China.
Sci Adv. 2023 Jul 28;9(30):eadh1789. doi: 10.1126/sciadv.adh1789.
Fast and high-resolution x-ray imaging demands scintillator films with negligible afterglow, high scintillation yield, and minimized cross-talk. However, grain boundaries (GBs) are abundant in polycrystalline scintillator film, and, for current inorganic scintillators, detrimental dangling bonds at GBs inevitably extend radioluminescence lifetime and increase nonradiative recombination loss, deteriorating afterglow and scintillation yield. Here, we demonstrate that scintillators with one-dimensional (1D) crystal structure, CsCuClI explored here, possess benign GBs without dangling bonds, yielding nearly identical afterglow and scintillation yield for single crystals and polycrystalline films. Because of its 1D crystal structure, CsCuClI films with desired columnar morphology are easily obtained via close space sublimation, exhibit negligible afterglow (0.1% at 10 ms) and high scintillation yield (1.2 times of CsI:Tl). We have also demonstrated fast x-ray imaging with 27 line pairs mm resolution and frame rate up to 33 fps, surpassing most existing scintillators. We believe that the 1D scintillators can greatly boost x-ray imaging performance.
快速且高分辨率的X射线成像需要余辉可忽略不计、闪烁产率高且串扰最小化的闪烁体薄膜。然而，多晶闪烁体薄膜中存在大量晶界，并且对于当前的无机闪烁体而言，晶界处有害的悬空键不可避免地会延长辐射发光寿命并增加非辐射复合损失，从而使余辉和闪烁产率变差。在此，我们证明具有一维（1D）晶体结构的闪烁体（本文所研究的CsCuClI）拥有无悬空键的良性晶界，其单晶和多晶薄膜的余辉和闪烁产率几乎相同。由于其1D晶体结构，通过近距离升华可轻松获得具有所需柱状形态的CsCuClI薄膜，其余辉可忽略不计（10毫秒时为0.1%）且闪烁产率高（是CsI:Tl的1.2倍）。我们还展示了具有27线对/毫米分辨率和高达33帧/秒帧率的快速X射线成像，超过了大多数现有的闪烁体。我们相信1D闪烁体能够极大地提升X射线成像性能。
