用低温溶剂热法以乙二醇为溶剂合成了Er3+和Yb3+共掺的In2O3纳米晶.用X射线衍射(XRD)、透射电镜(TEM)、漫反射光谱和上转换发光光谱对样品进行了分析.XRD和TEM结果表明,产物为纯的立方相In2O3结构,粒径约为30 am;漫反射光谱显示了In203:Er3+,yb3+纳米晶在522、653和975 nm附近有3个吸收带;在980 nm近红外光激发下,样品发射出中心波长为525及555 am的绿光和662 am的红光,分别对应于Er3+的2H11/2→4I15/2、4S4/2→4I15/2和4F9/2→4I15/2跃迁;研究了Er3+和Yb3+离子的不同掺杂浓度对发光强度的影响,确定了yb3+和Er3+离子的最佳掺杂浓度均为3%:双对数曲线显示绿光和红光的发射过程均为双光子吸收过程.对样品的上转换发光机制进行了初步讨论.%Nanocrystals of up-conversion phosphor Er3+ and Yb3+ co-doped In2O3 were prepared by solvent thermal method using glycol as solvent. The samples were characterized by X-ray diffraction, transmission electron microscopy, diffuse reflectance spectra, and upconversion luminescence spectra. X-ray diffraction analysis showed that the products were pure cubic phase,while transmission electron microscopy measurements confirmed the particles size was about 30nm. The diffuse reflectance spectra indicated that Er3+/Yb3+ co-doped In2O3 nanocrystals have three absorption bands around 522, 653 and 975 nm. Under 980 nm excitation, the spectral peaks centered at 525, 555, 662 nm respectively, corresponding to 2H11/2→4I15/2, 4S3/2→4I15/2 and 4F9/2→4I15/2 of Er3+ ions. The impact of different concentration of Er3+ and Yb3+ ions on the up-conversion luminescence intensity were discussed. When the doped concentration of Er3+ and Yb3+ ions are both 3％, the upconversion intensity got the most. The lgI-lgP curve shows that the green and red emissions are double-photon absorption process. And the upconversion mechanism and process of the samples were also analyzed.
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