Y_2O_3双掺杂Eu^(3+),Tb^(3+)的光谱性能及能量传递过程

Spectral Properties and Energy Transfer Process of Eu^(3+),Tb^(3+) Co-Doped Y_2O_3 Powders

采用溶胶凝胶法制备不同配比的Y2O3:Eu3+、Y2O3:Tb3+和Y2O3:Eu3+,Tb3+荧光粉。并通过XRD、SEM和激发、发射光谱对其结构和发光性能进行了研究,用能级图解释了激活剂之间的能量传递关系。结果表明,材料结晶良好,粒度分别为20、31nm和17nm左右,样品形貌类似片状结构。(Y110Eu)2kO3和(Y110Tb)2kO3配比时相对发光强度最高。而共掺杂时,存在着强烈的Eu3+向Tb3+的能量转移,导致红色发光强度的降低而敏化了绿光和蓝光的发射。分析可知,除了激活剂的含量对发光性能有强烈的影响之外,不同的激发波长对体系混合光的形成有很大的影响。当在305nm的激发波长下,可以得到红绿蓝混合光,实现了通过一种荧光粉的激发,发射出近白色的光。为改变灯用三基色荧光粉的组成并降低成本奠定了有利的实验基础。

In this paper,different proportions of Y2O3：Eu3＋、Y2O3：Tb3＋ and Y2O：Eu3＋,Tb3＋ fluorescent powders were prepared by sol-gel method. The structures and luminescence properties of powders were studied by XRD,SEM and excitation and emission spectra,and the effects of energy transfer between activators on luminescence properties were discussed through energy level scheme. The results showed that, the powder crystallized well, the average particle size of Y2O3：Eu3＋、Y2O3：Tb3＋ and Y2O：Eu3＋,Tb3＋ powders were about 20nm, 31nm and 17nm, respectively, and the sample morphology had similar sheet shape structures and the agglomeration phenomenon is obvious. In Eu3＋ or Tb3＋ single-doped Y2O3 system, the （Yl10 Eu）2k O3 and （Y110Tb） 2kO3 particles presented the highest luminescence intensity. While in Eu3＋ and Tb3＋ co-doping system, the strong energy transfer from Eu3＋ to Tb3＋ lead to the reduce of intensity of red light emission and increases of green and blue light emissions. It was found that besides the concentration of activator ions,the excitation wavelength had very important effects on the intensity of luminescence. When using 305nm as excitation wavelength,white light can be obtained with red,green and blue light mixed, realizing white light emission through exciting one fluorescent powder ,which also provide a feasible experimental basis for changing the composition of the trichromatic phosphor and reducing costs in aPPlication of lamp.