Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, 32306, USA.
Department of Nuclear Engineering, University of Tennessee, Knoxville, TN, 37996, USA.
Adv Mater. 2023 Jun;35(23):e2301612. doi: 10.1002/adma.202301612. Epub 2023 Apr 25.
Scintillators, one of the essential components in medical imaging and security checking devices, rely heavily on rare-earth-containing inorganic materials. Here, a new type of organic-inorganic hybrid scintillators containing earth abundant elements that can be prepared via low-temperature processes is reported. With room temperature co-crystallization of an aggregation-induced emission (AIE) organic halide, 4-(4-(diphenylamino) phenyl)-1-(propyl)-pyrindin-1ium bromide (TPA-PBr), and a metal halide, zinc bromide (ZnBr ), a zero-dimensional (0D) organic metal halide hybrid (TPA-P) ZnBr with a yellowish-green emission peaked at 550 nm has been developed. In this hybrid material, dramatically enhanced X-ray scintillation of TPA-P is achieved via the sensitization by ZnBr . The absolute light yield (14,700 ± 800 Photons/MeV) of (TPA-P) ZnBr is found to be higher than that of anthracene (≈13,500 Photons/MeV), a well-known organic scintillator, while its X-ray absorption is comparable to those of inorganic scintillators. With TPA-P as an emitting center, short photoluminescence and radioluminescence decay lifetimes of 3.56 and 9.96 ns have been achieved. Taking the advantages of high X-ray absorption of metal halides and efficient radioluminescence with short decay lifetimes of organic cations, the material design paves a new pathway to address the issues of low X-ray absorption of organic scintillators and long decay lifetimes of inorganic scintillators simultaneously.
闪烁体是医学成像和安检设备的重要组成部分之一,严重依赖于含稀土的无机材料。在此,报道了一种新型的可通过低温工艺制备的含丰富地球元素的有机-无机杂化闪烁体。通过室温共结晶具有聚集诱导发光(AIE)特性的有机卤化物 4-(4-(二苯基氨基)苯基)-1-(丙基)-1H-吡咯并[2,3-b]吡啶-1-溴化物(TPA-PBr)和金属卤化物溴化锌(ZnBr2),得到了零维(0D)有机金属卤化物杂化(TPA-P)ZnBr,其发射峰位于 550nm 处呈现出黄绿色。在这种杂化材料中,ZnBr2 通过敏化作用极大地增强了 TPA-P 的 X 射线闪烁性能。(TPA-P)ZnBr 的绝对光产率(14700±800 个光子/兆电子伏特)高于著名的有机闪烁体蒽(≈13500 个光子/兆电子伏特),而其 X 射线吸收与无机闪烁体相当。以 TPA-P 作为发光中心,其光致发光和辐射发光衰减寿命分别为 3.56 和 9.96ns。由于金属卤化物具有较高的 X 射线吸收能力和有机阳离子具有较短的辐射发光衰减寿命的优势,这种材料设计为同时解决有机闪烁体的低 X 射线吸收和无机闪烁体的长衰减寿命问题开辟了新途径。