High thermal stability and quantum yields of green-emitting Sr₃Gd₂(Si₃O₉)₂:Tb³⁺ phosphor by co-doping Ce³⁺

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• 作者：Yingli ZHU (朱颖丽)^a ; ^b ; Yujun LIANG (梁玉军)^a ; ^b ; ^{yujunliang@sohu.com} ; Shiqi LIU (刘仕琪)^a ; ^b ; Kai LI (李 恺)^a ; ^b ; Xingya WU (吴幸雅)^a ; ^b ; Rui XU (徐 瑞)^a ; ^b
• 关键词：Sr3Gd2(Si3O9)2 ; photoluminescence ; quantum yields ; thermal stability ; luminescence ; rare earths
• 刊名：Journal of Rare Earths
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：35
• 期：1
• 页码：41-46
• 全文大小：2541 K
• 卷排序：35

文摘

A series of Tb3+ mono-doped and Ce3+-Tb3+ co-doped Sr3Gd2(Si3O9)2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2(Si3O9)2:Tb3+ samples showed broad excitation spectrum from 250 to 400 nm and presented characteristic emission transitions 5D4→7FJ (J=6, 5, 4, 3) of Tb3+ under 313 nm excitation, which were located at about 488, 541, 584 and 620 nm. The emission intensities of Tb3+ rose steadily in Sr3Gd2(Si3O9)2 host with the increase of Tb3+ concentration even though Gd3+ ions were completely replaced by Tb3+ ions. The Ce3+ ion as a sensitizer could efficiently improve the performance of Tb3+ ion. First, with Ce3+ co-doping, the excitation spectrum of Tb3+ monitored at 541 nm showed a similar band that responds to the violet emission of Ce3+ monitored at 416 nm. Second, the quantum yields of Sr3Gd2(Si3O9)2:Tb3+ phosphors could be enhanced from 26.6% to 80.2% by co-doping Ce3+. Finally, the co-doping of Ce3+ was also effective to improve the thermal stability of Sr3Gd2(Si3O9)2:Tb3+. As the temperature rose to 150 °C, the emission intensity of Tb3+ remained at about 83.6% of that measured at room temperature, which was better than the commercial YAG:Ce phosphor in terms of their thermal quenching properties. These results indicated that the as-prepared Sr3Gd2(Si3O9)2:Tb3+,Ce3+ samples could be used as green emission phosphors for possible applications in near ultraviolet based WLEDs.