微波场作用下Y_2O_2S:Tb绿色荧光粉的快速合成及其发光特性

Rapid Synthesis and Luminescent Properties of Y_2O_2S:Tb Green-Emitting Phosphors by Microwave Radiation

采用微波法快速合成了Y2O2S：Tb绿色荧光粉。用X射线衍射（XRD）仪、扫描电镜（SEM）、荧光分光光度计等对合成产物的相结构、形貌、以及发光特性进行了研究。结果表明：材料的晶体结构为六方晶系，与Y2O2S相同。颗粒的形貌为类球形，分散性很好，平均晶粒尺寸在300nm左右。发射光谱由384，418，439，460，475，498，547，590，624nm等一系列窄带发射峰组成，归属于Tb^3＋从^5D3，^5D4到^7FJ（J=0～6）的跃迁。研究发现Tb的掺杂浓度对样品的发射光谱有着很重要的影响，当其浓度为0．5％（摩尔分数，下同）时，^5D3→^7FJ的蓝光发射发生猝灭，当其浓度为9％时，^5D4→^7FJ的绿光发射发生猝灭。

Y2O2S：Tb, green-emitting phosphors were firstly synthesized in microwave felid for the reaction time of only 20 min. The crystal structure, morphology and luminescence properties of as-synthesized Y2O2S：Tb phosphors were investigated by X-ray diffraction, SEM and fluorescence spectrophotometer, respectively. The results show that the crystal structure of as-synthesized Y2O2S：Tb phosphors is hexagonal, similar to that of Y2O2S. The particles of as-synthesized phosphors are basically spherical in shape, and well dispersed with the mean particle size of 300 nm. The emission spectrum is composed of a series of sharp peaks, located at 384 nm, 418 nm, 439 nm, 460 nm, 475 nm, 498 nm, 547 nm, 590 nm, 624 nm, respectively. These emission peaks are ascribed to Tb^3＋ ions transition from ^5D3, ^5D4 to ^7FJ （J = 0-6）. It is found that the Tb^3＋ concentration has a significant effect on the emission spectrum. When Tb^3＋ concentration is 0.5 mol%, the blue emission （^5D3→^7FJ） quenched, and the green emission （^5D4→^7FJ） quenched at the Tb^3＋ concentration of 9 mol%.