Dy^(3+)/Tb^(3+)共掺杂LaF_3微纳米球的水热合成及其发光性质

Hydrothermal Synthesis and Luminescence Properties of Dy^(3+)/Tb^(3+) co-doped LaF_3 Micro-nanospheres

采用水热法制备了稀土离子掺杂LaF_3:Ln^(3+)(Ln=Tb^(3+),Dy^(3+)和Dy^(3+)/Tb^(3+))荧光材料,通过XRD、SEM、FL分别对样品的结构、形貌和荧光性能进行表征.实验结果表明样品为纯六方晶系LaF_3纳米微球.研究了不同的pH值、Tb^(3+)不同摩尔掺杂浓度对LaF_3:Tb^(3+)发光性质的影响.结果显示在水热为160℃,24h,pH=3条件下制备的LaF_3:7.5%Tb^(3+)荧光强度最强(Tb^(3+)的特征发射峰位于489 nm、543 nm、585 nm和621 nm处),当Tb^(3+)的摩尔掺杂浓度大于7.5%时,将导致荧光猝灭.研究了Dy^(3+)/Tb^(3+)共掺杂La F3的光谱性质,结果表明,Dy^(3+)作为敏化剂,能有效敏化Tb^(3+)的特征发光,其能量传递方式为非辐射共振传递.少量的Dy^(3+)掺入到LaF_3:Tb^(3+)中,可使其543nm处的Tb^(3+)荧光强度显著增强.

Rare earth ions doped LaF3：Ln^3＋（Ln= Tb^3＋, Dy^3＋ and Dy^3＋/Tb^3＋） were synthesized by hydrothermal method. The properties were characterized by XRD, SEM and FL. XR.D pattern and SEM shows that the synthesized samples were pure hexagonal phase LaF3 micro-nanospheres. The luminescent properties of LaF3：Tb^3＋ have been systematically investigated at different reaction pH, and different molar ratio of Tb^3＋. The obtained LaF3：7.5 mol%Tb^3＋, synthesized at 160℃, 24h, and pH=3, exhibited the highest luminescence intensity at 489nm, 543nm, 585nm and 621nm. The results indicate that the concentration quenching occur when the Tb^3＋ ion concentration is up to 7.5mol%. And also study the luminescence properties of LaF3： Dy^3＋/Tb^3＋. The results shows that the Dy^3＋ ions can effectively sensitize Tb^3＋ activator by non-radiation energy transfer in LaF3. The emission intensity ofLaF3：Tb^3＋, as co-doped with a spot of Dy^3＋, was significantly enhanced at 543nm.