稀土掺杂的NaGdF_4上转换发光材料的合成与发光特性研究  

Synthesis and Luminescence Properties of Rare Earth Doped NaGdF_4 Upconversion Phosphors

作　　者：李艳红[1] 臧国凤 马晶[1] 刘宇田[1] 

机构地区：[1]沈阳化工大学材料科学与工程学院,辽宁沈阳110142

出　　处：《发光学报》2013年第8期982-987,共6页Chinese Journal of Luminescence

基　　金：辽宁省教育厅科学技术研究项目(L2011063)资助项目

摘　　要：采用水热法制备了一系列不同掺杂浓度的NaGdF4:Re(Re=Tm3+,Er3+,Yb3+)上转换发光粉。通过X射线衍射(XRD)、电子扫描电镜(SEM)和上转换发射光谱对样品进行了表征。XRD研究结果表明:合成的样品均为六方结构NaGdF4。估算的平均晶粒尺寸为41～43 nm。在980 nm红外光激发下,Er3+和Yb3+共掺杂的NaGdF4发光粉发出分别来自于Er3+离子2H11/2,4S3/2→4I15/2跃迁的绿光和4F9/2→4I15/2跃迁的红光发射,Tm3+和Yb3+共掺杂的NaGdF4发光粉发出分别来自Tm3+离子的1G4→3H6跃迁的蓝光、1G4→3F4和3F2,3→3H6跃迁的红光和3H4→3H6跃迁的近红外光发射。Er3+,Tm3+和Yb3+共掺杂的NaGdF4发光粉的发光强度及红、绿、蓝光发射的相对强度受Yb3+离子掺杂浓度的影响。对样品中可能的上转换发光机制进行了讨论。计算的色坐标显示:可通过改变掺杂离子浓度对上转换发光的颜色进行调控。A series of NaGdF4:Re(Re=Tm3+,Er3+,Yb3+) upconversion luminescence phosphors with various doping concentrations were prepared by a hydrothermal method.X-ray diffraction(XRD),field emission scanning electron microscope(SEM) and upconversion(UC) emission spectra were used to characterize the samples.The results of XRD indicate that all the samples are hexagonal phase NaGdF 4.The average crystallite sizes are estimated to be 41～43 nm.Under 980 nm laser excitation,the Er3+ and Yb 3 + codoped NaGdF4 phosphors show green emission from 2H11/2→4I15/2 and 4S3/2→4I15/2 transitions of Er3+ ions,the red emissions attributed to 4F9/2→4I15/2 transitions of Er3+ ions,respectively.The Tm3+ and Yb3+ codoped NaGdF4 phosphors show blue emission from 1G4→3H6 transitions of Tm3+ ions,red emission assigned to 1G4→3F4 and 3F2,3→3H6 transitions of Tm3+ ions,near-infrared corresponding to the 3H4→3H6 transitions of Tm3+ ions,respectively.The upconversion luminescence intensity and a relative intensity of red,green and blue emission are governed by the doping Yb3+ concentrations in Er3+,Tm3+ and Yb3+ tridoped NaGdF4 phosphors.The possible upconversion luminescence mechanisms of the samples are discussed.The calculated CIE color coordinates display that the upconversion luminescence color can be tuned by varying the doping ions concentration.

关 键 词：NaGdF4:Re 水热法 发光粉 上转换发光 

分 类 号：O482.31[理学—固体物理]