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利用硫熔法制备了不同浓度的Yb和Ho掺杂的Y2O2S:Yb,Ho上转换发光材料。采用X线衍射仪、扫描电镜和荧光光谱仪对粉体的相组成、形貌和上转换发光性能进行表征。结果表明:不同浓度的Yb和Ho掺杂后没有改变Y2O2S的晶体结构;颗粒形貌较为规则,多呈现多面体状,分散性较好,颗粒表面很光滑;在980nm激光激发下,Y2O2S:Yb,Ho呈现出以绿光发射为主的上转换荧光,Yb的最佳掺杂量为8%(摩尔分数),Ho的最佳掺杂量为2%(摩尔分数),Ho3+和Yb3+掺杂浓度可显著影响不同颜色发射峰的强度;对激活离子Ho3+来说,同类离子之间发生能量传递和交叉弛豫行为,导致上转换荧光强度发生猝灭;对敏化离子Yb3+来说,Yb3+吸收能量,以热的形式释放出来,产生杂质猝灭。
Different Yb and Ho doped Y2O2S: Yb, Ho up-conversion luminescent materials were prepared by sulfur melting method. X-ray diffractometry, scanning electron microscopy and fluorescence spectroscopy were used to characterize the phase composition, morphology and upconversion luminescence of the powders. The results show that Yb and Ho do not change the crystal structure of Y2O2S after doping with different concentrations. The morphology of Y2O2S is regular and polyhedron with good dispersibility and smooth surface. Under 980nm laser excitation, Y2O2S: Yb, Ho shows up-conversion fluorescence with green emission as the best doping amount of Yb is 8% (mole fraction), the optimal doping amount of Ho is 2% (mole fraction), Ho3 + and Yb3 + doping concentration Can significantly affect the intensity of the emission peaks of different colors; for the activated ion Ho3 +, the energy transfer and cross relaxation behavior occur between the same ions, resulting in the quenching of the upconversion fluorescence intensity; for the sensitizing ion Yb3 +, Yb3 + absorption energy , Released in the form of heat, resulting in impurity quenching.