Solvothermal synthesis and upconversion properties of about 10 nm orthorhombic LuF3: Yb3+, Er3+ rectangular nanocrystals
Solvothermal synthesis and upconversion properties of about 10 nm orthorhombic LuF3: Yb3+, Er3+ rectangular nanocrystals
复制标题
约10 nm正交LuF3: Yb3 , Er3矩形纳米晶的溶剂热合成及其上转换性能
DOI：
10.1016/j.jcis.2015.08.026
复制
发表时间：
2015-12-01
影响因子：
9.9
通讯作者：
Zhao, Haifeng
中科院分区：
文献类型：
--
作者：
Xiang, Guotao;Zhang, Jiahua;Zhao, Haifeng
采用简单有效的溶剂热法合成了尺寸约为10 nm的Yb3+、Er3+共掺正交型纳米LuF3(NCS)。用X射线衍射仪、透射电子显微镜、高分辨电子显微镜、上转换发光光谱和衰减曲线对样品进行了表征。与YF3和α-NaYF4 NCS相比，在尺寸和Yb3+离子和Er3+掺杂水平与LuF3 NCS相同的情况下，LuF3 NCS的绿光发射分别是YF3和α-NaYF4 NCS的18.7倍和5.1倍，红光UC发射分别是YF3和α-NaYF4 NCS的13.2倍和0.6倍。在980 nm波长激发下，S-4(3/2)->；I-4(15/2)跃迁和F-4(9/2)->；I-4(15/2)跃迁的衰减曲线均呈单指数函数关系，这是由于高浓度Yb3+离子(20%)引起Yb3+离子间的快速能量迁移所致。同时，在相对较低的功率密度下，绿色UC和红色UC的Log(I)和Log(P)之间的线性曲线斜率分别为1.7和1.9，由于热效应的猝灭，斜率小于2，表明它们是一个双光子过程。在高功率密度下，饱和效应引起的斜率减小。此外，我们还证明了热效应的存在。根据H-2(11/2)->；I-4(15/2)跃迁到S-4(3/2)->；I-4(15/2)跃迁光强比随抽运功率的变化关系。(C)2015 Elsevier Inc.保留所有权利。
The Yb3+ and Er3+ codoped orthorhombic LuF3 rectangular nanocrystals (NCs) with the size of about 10 nm were synthesized by a facile and effective solvothermal process. X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), upconversion (UC) luminescence spectra and decay curves were used to characterize the resulting samples. Compared with YF3 and alpha-NaYF4 NCs, owning the similar size and the same doping levels of Yb3+ ions and Er3+ ions as LuF3 NCs, the green UC emission of LuF3 NCs is 18.7 times and 5.1 times stronger than that of YF3 and of alpha-NaYF4 NCs respectively; the red UC emission of LuF3 NCs is 13.2 times and 0.6 times stronger than that of YF3 and alpha-NaYF4 NCs respectively. Under 980 nm wavelength excitation, the decay curves of both S-4(3/2) -> I-4(15/2) transition and F-4(9/2) -> I-4(15/2) transition exhibit a single exponential function, resulting from the fast energy migrations among Yb3+ ions caused by the high concentration of Yb3+ ions (20 mol%). Meanwhile, at relatively low power density, the slopes of the linear plots between log(I) and log(P) for green UC and red UC are 1.7 and 1.9 respectively, which are less than 2 due to the quenching of the thermal effect, indicating a two-photon process for them. At high power density, the slopes are decreased caused by the saturation effect. In addition, we proved the existence of the thermal effect. by the pump power dependence of the intensity ratio of H-2(11/2) -> I-4(15/2) transition to S-4(3/2) -> I-4(15/2) transition. (C) 2015 Elsevier Inc. All rights reserved.