摘要
采用微波法快速合成了La2O2S:Tb绿色荧光粉。用X射线粉末衍射(XRD)、扫描电镜(SEM)、荧光分光光度计等对合成产物的结构、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La2O2S的相同。颗粒的形貌多为六边形,分散性很好,尺寸在2μm左右。发射光谱由498nm、547nm、590nm、624nm等一系列窄带发射峰组成,归属于Tb^3+从^5D4到^7FJ(J=0~6)的跃迁。主发射峰位于547nm,对应于^5D4→^7F5的能级跃迁,导致一种绿光发射。研究发现Tb的掺杂浓度对样品主发射峰的发光强度有着很重要的影响,在7%(摩尔分数)时达到最大,继续增加Tb的浓度,发光强度反而降低。
La2O2S : Tb, green-emitting phosphors were synthesized in microwave field. Reaction time was only 20min. The crystal structure,morphology and luminescence properties of as-synthesized La2O2S : Tb were investigated by x-ray diffraction, SEM and fluorescence spectrophotometer respectively. The results show that the crystal structure of as-synthesized La2O2S : Tb is hexagonal,which is similar to that of La2O2S. The particles of as-synthesized phosphor are basically hexagonal in shape, and dispersing well. The emission spectrum is composed by a series of sharp peaks ,located at 498nm, 547nm, 590nm, 624nm respectively. These emission peaks are ascribed to Tb^3+ transition from ^5D4 to ^7FJ (J= 0-6). The main emission peak is at 547nm (^5D4→&7F5), which results in a green-emitting. It is also found that the molar ratio of Tb^3+ plays a very important role in the emission spectrum. When the molar ratio of Tb^3+ is 7%, the green emitting becomes strongest. Further increasing the molar ratio of Tb^3+, the green emitting becomes weak.
出处
《稀土》
EI
CAS
CSCD
北大核心
2007年第2期23-25,29,共4页
Chinese Rare Earths
基金
河北省教育厅博士基金资助项目(B2004205)
河北省科学技术研究与发展计划项目(06213015)
河北大学研究基金资助项目