为得到最大发光强度的 Tm3+/Yb3+共掺钼酸钇钠荧光粉,采用试验优化设计的方法建立发光强度与Tm3+/Yb3+掺杂浓度的回归方程,再通过遗传算法优化算出方程的最大解。利用高温固相法制备出了该解的Tm3+/Yb3+共掺钼酸钇钠荧光粉样品。在980 nm抽运激发下,测量了样品的上转换荧光发射谱,分析了上转换发光机制,在室温下观察到强烈的蓝光(476 nm)和微弱的红光(649 nm)发射,其分别对应于Tm3+的1G4→3H6和1G4→3F4跃迁。在Tm3+/Yb3+上转换发光体系中,1G4的上转换可见发射是双光子合作上转换能量传递过程。并探讨了样品的温度效应,发现该样品蓝光发光强度随温度升高而减弱,并对其温度猝灭机理进行了解释。%The method of optimally designing experiments is introduced to study the properties of up-conversion luminescence in Tm3+/Yb3+co-doped NaY(MoO4)2 phosphors. The design of experiment, data analysis and objective are all optimized. Uniform design is used to seek for the doping concentration range, and quadratic general rotary unitized design is included to build the equation between the luminescent intensity and the Tm3+/Yb3+doping concentration. In order to obtain the best luminescent intensity, genetic algorithm is introduced into our calculation. The optimal Tm3+/Yb3+ co-doped NaY(MoO4)2 phosphor is synthesized by high temperature solid state method. The up-conversion emission spectrum under the 980 nm laser excitation is detected and the luminescence mechanism is proposed. We observe intense blue light (476 nm) and week red light (649 nm) at room temperature, which are emitted from the Tm3+transition of 1G4→ 3H6 and 1G4→ 3F4, respectively. In this up-conversion luminescence system, the up-conversion emission of 1G4 is due to the cooperation energy transfer of two photons. We also discuss the temperature effect of the sample, and as the temperature increases its luminescent intensity decreases.
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