发光二极管用荧光材料Sr_2CeO_4：Sm^(3+)的合成及其发光特性

Synthesis and Luminescent Characteristics of Sr_2CeO_4:Sm^(3+) Phosphors for Light-emitting Diode

以具有一维结构的Sr_2CeO_4化合物为研究对象、Sm^(3+)作为发光中心,探索了其作为LED用荧光材料的可能性.用高温固相法于1200℃、6h合成了Sr_2CeO_4:Sm^(3+)系列单相粉末样品,并研究了其发光性质.结果表明,在365nm激发下,从荧光光谱中可以看出存在从基质向稀土离子的能量转移.通过调节荧光材料Sr_2CeO_4:Sm^(3+)中稀土离子Sm^(3+)的掺杂浓度,可以调谐发光体的发光颜色,当Sm^(3+)离子浓度较小(<3%)时,体系发出很强的白光;当Sm^(3+)离子浓度较大(3%～15%)时,体系发出红光.测量了荧光材料的色坐标,发现Sr_2CeO_4:1%Sm^(3+)的色坐标是(0.334,0.320),接近于纯白色(0.33,0.33),可以作为一种新型的UV-LED用单一白色荧光材料.

The trivalent samarium doped Sr2CeO4 color-tunable phosphors were successfully synthesized by solid state reaction at 1200℃ for 6h and their luminescent characteristics were studied. The results indicate that the host can transfer its exciting energy to rare earth ion Sm^3＋ when excited with 365nm light. The emission color can be changed by tuning activator＇s concentration in Sr2CeO4：Sm^3＋ phosphors. The doped compound emits strong white light when the concentration of the doped Sm^3＋ is lower than 3%. When the Sm^3＋ concentration is increased from 3% to 15%, it emits red light. The chromaticity coordinate of Sr2CeO4： 1%Sm^3＋ phosphor is measured to be （x, y） （0.334, 0.320）, which is closed to the pure white （0.33, 0.33）. It shows that Sr2CeO4： 1%Sm^3＋ phosphor is a promising single white phosphor for ultraviolet light-emitting diode.