铀基X射线闪烁体研究进展

Research Progress on Uranyl-Bearing X-Ray Scintillator

贫铀再利用是近年来放射化学领域尤为关注的课题,研究发现以铀酰离子作为金属中心合成的含铀晶体材料在X射线辐照场中产生强烈的闪烁现象。与传统闪烁发光元素相比,铀元素具有发光效率高、辐射阻滞能力强等本征属性,为发展新型闪烁体提供了物质基础。近期研究合成的新型铀基闪烁体显现出较高的X射线转换效率、强X射线衰减系数、较好的辐照与湿度稳定性、以及更短的余辉等优势。本文从铀酰发光原理、铀基晶体闪烁现象的发现、含铀闪烁体材料的优势出发,主要阐述了基于铀酰本征性质的新型铀基闪烁体用于X射线探测方面的研究进展,提出了提高含铀闪烁体性能的方法思路。研究成果既为处理贫铀资源提供了新的途径,又为高性能新型闪烁体的设计提供了借鉴。

Resource utilization of depleted uranium is an emerging research subject in the field of radiochemistry. The development of new uranium-bearing functional materials is an alternative route. The authors recently discovered the intense X-ray scintillating phenomenon of uranyl-bearing crystals under X-ray irradiation. Compared to the intensity investigated emitters in conventional scintillators, high emissive nature and high radiation stopping power are the intrinsic features for the uranyl ions, which make them promising in the development of scintillator. In recent works, uranyl-bearing scintillators showed high X-ray-to-luminescence conversion efficiency, high X-ray excited luminescence(XEL), strong X-ray attenuation coefficient(XAC), reduced afterglow as well as decent radiation and hygroscopy hardness. In this contribution, the research progress on the uranyl-bearing X-ray scintillator is reviewed. We will discuss the luminescence mechanism, the discovery of scintillating phenomenon of uranyl, and intrinsic advantages based on the uranyl-bearing scintillators, leading us find the idea how to improve the performance of uranyl-bearing scintillator. This work will provide a new strategy for resource utilization of depleted uranium based on the development of uranyl-based optical materials. In addition, we put forward a new route for further designing scintillators with high X-ray detection performance.