Lu_2O_3∶Tb纳米粉末的光致发光特性  

Photoluminescent Properties of Nanocrystalline Lu_2O_3∶Tb

作　　者：徐美[1] 张慰萍[2] 江寅[2] 董宁[2] 尹民[1] 

机构地区：[1]中国科学技术大学结构分析重点实验室,安徽合肥230026 [2]中国科学技术大学物理系,安徽合肥230026

出　　处：《发光学报》2005年第5期581-586,共6页Chinese Journal of Luminescence

基　　金：国家"863"计划(2002AA324070);国家自然科学基金(50332050)资助项目

摘　　要：用燃烧合成法制备了Lu2O3:Tb3+纳米粉末.产物为立方相结构,粒径在3～40nm之间可控.对不同颗粒度的样品的激发光谱、发射光谱和荧光衰减特性进行了研究.在紫外光激发下,样品显示出较强的发光(来自于Tb3+的5D3,4→7FJ跃迁).同时,样品的光致发光性质在很大程度上受到样品颗粒度的影响,对此现象给出了合理的解释.As the rapid development of high-energy physics and nuclear medical technology, there has been a great growth of interest in lutetium-based compounds such as lutetium silicate, lutetium aluminate and lutetium oxide. High Z number （Z = 71 ） of Lu, high physical and chemical stability and high luminescent efficiency of these compounds make them extremely attractive for application in scintillator materials, especially in medical applications. Nanocrystalline Lu2 O3 ： Tb was high-resolution electronic microscope prepared by combustion synthesis. X-ray diffraction （XRD） （HREM） photographs, Fourier transform infrared spectroscopy spectra, （FF-IR）,excitation and emission spectra, as well as fluorescent decay curves were measured to characterize the structure and luminescent properties of the samples. The results show that the compound of composition Lu2 O3 crystallizes in pure cubic structure. By changing the ratio of glycine to nitrate in the combustion process, the particle size can be controlled in the range from 40 nm to 3nm, and the amorphous area increases while the grain size decreases, which plays an important role in the luminescence properties. Photoluminescence spectra and fluorescent decay curves measured under room temperature show typical excitation and emission peaks of Tb^3＋. Under UV excitation, the relative intensity of s ^5D3.4→^7F1 increases with the decreasing of particle size because of the weakened cross-relaxation process in small-size samples. In the sample smaller than 10 nm, the efficiency of energy transfer from host lattice to the activator ions decreases sharply, and there presents a new decay composition of 0.63 ms for the ^5D4 energy level, besides the normal one is about 1. 9 ms.

关 键 词：纳米Lu2O3:Tb 光致发光 荧光寿命 

分 类 号：O482.31[理学—固体物理]