超薄金壳包覆NaYF4∶Yb,Er@SiO2纳米结构的可控合成与表面增强上转换荧光  

Controllable Synthesis and Surface-enhanced Upconversion Luminescence of Ultra-thin Gold Shell Coated NaYF_4∶Yb,Er@SiO_2 Nanostructures

作　　者：安西涛 王月[1] 牟佳佳 李静[1] 张立功[3] 骆永石[3] 陈力[1] AN Xi-tao;WANG Yue;MU Jia-jia;LI Jing;ZHANG Li-gong;LUO Yong-shi;CHEN Li(School of Chemistry and Life Science,Advanced Institute of Materials Science,School of Basic Science,Changchun University of Technology,Changchun 130012,China;School of Physics,Beihua University,Jilin 132013,China;State Key Laboratory of Luminescence and Applications,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]长春工业大学化学与生命科学学院,材料科学高等研究院,基础科学学院,吉林长春130012 [2]北华大学物理学院,吉林吉林132013 [3]发光学及应用国家重点实验室,中国科学院长春光学精密机械与物理研究所,吉林长春130033

出　　处：《发光学报》2018年第11期1505-1512,共8页Chinese Journal of Luminescence

基　　金：国家自然科学基金(11474035,11504029);吉林省科技厅项目(20170520110JH,20170520108JH)资助。

摘　　要：利用原位还原法成功制备了尺寸均一、超薄完整金壳包覆的NaYF_4∶Yb,Er@SiO_2@Au(NSA)纳米结构,其XRD、TEM、EDX、HRTEM-HAADF、Mapping及吸收光谱表征结果表明,SiO_2壳及纳米金壳的平均厚度分别约为5nm和2nm。在980nm连续激光激发下,系统研究了核壳结构的上转换荧光强度与氯金酸浓度的依赖关系。稳态光谱结果显示,NSA与仅SiO_2包覆样品(NS)相比Er^(3+)的红绿荧光强度均增强了~2.8倍。通过分析上转换荧光动力学过程及利用FDTD方法模拟,讨论了表面等离激元增强上转换荧光的机制。The in-situ reduction method was successfully used to prepare the uniform and ultrathin gold shell-coated NSA nanostructures.The microstructure and composition characterizations such as XRD,TEM,EDX,HRTEM-HAADF,mapping as well as absorption spectra data indicated that the average thicknesses of SiO2 shell and gold nanoshell are about 5 nm and 2 nm,respectively.Under the excitation of a CW diode laser of 980 nm,the dependence of the upconversion fluorescence intensity of the core-shell structure on the concentration of chloroauric acid was systematically investigated.The steady-state spectral results show that the red and green upconversion luminescence intensities of NS samples are 2.8 times enhanced simultaneously by coating the gold shell.The upconversion lifetime of the red and green emission levels before and after the gold shell cladding is obtained by fitting the fluorescence decay curves.The mechanism of enhanced upconversion fluorescence by the surface plasmons is discussed based on the spectral analysis and FDTD method simulation.

关 键 词：上转换发光 纳米金壳 表面等离激元 能量传递 表面增强荧光 

分 类 号：O482.31[理学—固体物理]