新型绿色发光材料Sr_2ZnSi_2O_7:Tb^(3+)的制备及发光性质

Preparation and luminescent properties of novel green-emitting phosphors Sr_2ZnSi_2O_7:Tb^(3+)

采用微波辅助凝胶-燃烧法成功地合成了Sr2ZnSi2O7:Tb3+硅酸盐绿色发光材料.通过X线粉末衍射表征了材料的物相结构,用荧光分光光度计表征了材料的光致发光性能,同时对Tb3+浓度及助熔剂H3BO3用量等对材料发光性质的影响进行了研究.结果表明:该材料与Sr2ZnSi2O7具有相同的晶体结构,同属四方晶系.Sr2ZnSi2O7:Tb3+的激发光谱由位于200~300nm的1个宽带和位于325~400nm的1组窄峰组成,前者属于Tb3+4f8→4f75d的跃迁,后者由Tb3+离子的f→f跃迁引起;样品的发射光谱由位于414,436,490,543,584nm处的一系列窄带发射峰组成,均属于Tb3+的特征发射.其中,543nm处发射峰最强,因而样品发绿光.同时,确定了Tb3+的最佳掺杂量为摩尔分数x(Tb3+)=0.08,H3BO3的最佳用量摩尔分数x(H3BO3)=0.15.

Novel silicate green-emitting phosphors SrzZnSi2OT：Tba＋ were synthesized by microwave- assisted gel-combustion method. The phase structure o{ the phosphors was characterized by X-ray diffrac- tion, and photo-luminescent properties were investigated by Fluorescence spectrophotometer. Meanwhile, the effects of Tb3＋ concentration and flux H3 BO3 dosage on luminescence properties of the phosphors were studied. The results showed that Sr2ZnSi2OT：Tb3＋ phosphors possessed the similar tetragonal crystal structure as that of Sr2ZnSi2OT. The excitation spectrum of SrzZnSi207 ： Tb3＋ was composed of a broad band from 200 nm to 300 nm and a series of narrow peaks from 325 nm to 400 nm. The former could be as- cribed to 4fs--,＇4f75d transition of Tb3＋ , and the latter was due to f→f transition of Tb3＋. The emission spectrum was composed of a series of peaks, located respectively at 414, 436,490, 543, 584 nm. All these emission peaks could be ascribed to the characteristic f→f transitions of Tb3＋. The strongest emission peak was at 543 nm,showing green-emitting. In addition, it was confirmed that the optimum concentration of doped Tb3＋ was x（Tba＋）-0. 08, and the optimum dosage of H3BO3 was x（H3BO3）=0.15.