Liu Lulu, Li Weijun, Feng Xiaopeng, Guo Chunjie, Zhang Huimao, Wei Haotong, Yang Bai
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
Department of Radiology, The First Hospital of Jilin University, Changchun, 130061, P. R. China.
Adv Sci (Weinh). 2022 May;9(15):e2103735. doi: 10.1002/advs.202103735. Epub 2022 Mar 23.
Metal halide perovskite scintillators encounter unprecedented opportunities in indirect ionizing radiation detection due to their high quantum yields. However, the long scintillation lifetime of microseconds upon irradiation, known as the afterglow phenomenon, obviously limits their fast development. Here, a new type of hybrid X-ray detector wafer combining direct methylamine lead iodide (MAPbI ) semiconductor and indirect zero-dimensional cesium copper iodide (Cs Cu I ) scintillator through low-cost fast tableting processes is reported. Due to the fast energy transfer from Cs Cu I to MAPbI , the device response time to X-rays is dramatically reduced by nearly 30 times to 36.6 ns, which enables fast X-ray detection capability by a large area detector arrays within 1 s. Moreover, Cs Cu I exists at the grain boundaries of MAPbI crystals, and blocks the paths of mobile ions of perovskite, leading to the lowest detectable dose rate of hybrid X-ray detector is thus reduced by 1.5 times compared with control MAPbI direct-type semiconductor, and 10 times compared with the Cs Cu I indirect-type scintillator. The direct/indirect hybrid wafer also exhibits improved operation stability at ambient conditions without any encapsulation. This new kind of hybrid X-ray detectors provides strong competitiveness by combining the advantages of both direct perovskite semiconductors and indirect perovskite scintillators for next-generation products.
金属卤化物钙钛矿闪烁体因其高量子产率在间接电离辐射探测中面临前所未有的机遇。然而,辐照后微秒级的长闪烁寿命,即所谓的余辉现象,明显限制了它们的快速发展。在此,报道了一种新型的混合X射线探测器晶圆,它通过低成本的快速压片工艺将直接型甲基碘化铅(MAPbI)半导体和间接型零维碘化铯铜(CsCuI)闪烁体结合在一起。由于从CsCuI到MAPbI的快速能量转移,该器件对X射线的响应时间大幅缩短近30倍至36.6纳秒,这使得大面积探测器阵列能够在1秒内实现快速X射线探测能力。此外,CsCuI存在于MAPbI晶体的晶界处,阻挡了钙钛矿中移动离子的路径,导致混合X射线探测器的最低可探测剂量率与对照MAPbI直接型半导体相比降低了1.5倍,与CsCuI间接型闪烁体相比降低了10倍。这种直接/间接混合晶圆在无任何封装的环境条件下也表现出更好的运行稳定性。这种新型混合X射线探测器通过结合直接钙钛矿半导体和间接钙钛矿闪烁体的优点,为下一代产品提供了强大的竞争力。