BaGd2O4:Eu3+闪烁体余辉特性有效调控的研究

高密度闪烁体在高能物理工程、核医学成像、国家安全及国际反恐等高科技领域中都获得了成功的应用，但激活剂浓度偏低、大尺寸晶体生长困难且成本昂贵、余辉特性存在等实际问题限制了高密度闪烁体的进一步推广应用。为解决实用闪烁体余辉特性有效调控这一科学问题，本项目以较为廉价的BaO-Gd2O3二元系为基础，采用高温固相法合成具备自主知识产权的高密度BaGd2O4:Eu3+闪烁体，通过异价离子共掺和同价离子替代等方法调控BaGd2O4:Eu3+闪烁体的微结构进而有效调节其余辉特性，借助现代材料科学表征手段及固体发光理论系统研究BaGd2O4:Eu3+闪烁体微结构及其发光性能（尤其是余辉特性）间的相互关联，运用Judd-Ofelt理论评价BaGd2O4基质中局域环境与Eu3+的相互作用机制，重点构建闪烁材料余辉特性有效调控的物理模型，为丰富和发展新型高效闪烁材料提供关键性的实验参数和理论依据。

Dense scintillating materials have been sucessfully applied in various high-level scientific fieds such as high energy physics engineering, nuclear medical image, nation safeguard and international antiterrist activity. Some practical problems including low concentration of dopant activators, difficulty in growing large-dimension crystals with expensive cost,and the troublesome afterglow characteristics have inhibited extensive application of the developed scintillating materials. To control effectively the afterglow characteristics of practical scintillators, dense BaGd2O4:Eu3+ scintilating phosphors with self-owned intellectual property will be designed and developed by relatively enconimic and desne BaO-Gd2O3 binary system, and their microstructure will be tuned by alivolant ion codoping and isovalent ion substitution methods. The correlation between micrstructure and optical performances (especially in afterglow characteristics) will be systematically revealed by modern characterization technologies of material science and luminensece theory. The interaction mechanism between the local enviromental of BaGd2O4 host material and the luminescent Eu3+ ions will be evaluated by the famous Judd-Ofelt theroy, and the corresponding physics model on the controlled afterglow charactersitcs of scintillating materials is finally constructed. The obtained valuable resutls will be a instructive guidance to the enrichment and development of nonvel scintillating materilas in both experiment designing and theory improvement.