稀土离子Ce,Tb掺杂硼磷酸锶荧光粉的发光性质

采用高温固相法合成了2SrO·0.25B₂O₃·0.75P₂O₅:RE³⁺(RE=Ce,Tb)荧光粉。研究了其中Ce³⁺,Tb³⁺的光谱性质,Ce³⁺和Tb³⁺共掺杂时的能量传递效率,以及Ce³⁺和Tb³⁺的动力学过程。发现在共掺杂的样品中,Tb³⁺的⁵D₄→⁷F₅绿色发射比Tb³⁺单掺杂样品中的绿色发射有显著的提高。当Tb³⁺的含量从1%增加到8%时,Ce³⁺→Tb³⁺的能量传递效率逐渐增加至70%。通过动力学研究,在Ce³⁺和Tb³⁺共掺杂的样品中,提高Tb³⁺的浓度,Ce³⁺的寿命减小。此外,Ce³⁺离子寿命的倒数与Tb³⁺的浓度之间很好地符合线性函数关系,经过拟合Ce³⁺离子的电子跃迁速率和Ce³⁺→Tb³⁺的能量传递速率分别为5.1×10^-2和1.34ns^-1·mol^-1。Tb³⁺的⁵D₄→⁷F₅跃迁的衰减曲线很好地遵守指数式衰减,并且随着Ce³⁺的掺杂浓度提高,Tb³⁺的⁵D₄→⁷F₅寿命增加。结果表明在共掺杂的2SrO·0.25B₂O₃·0.75P₂O₅材料中存在Ce³⁺到Tb³⁺的有效能量传递,这种材料在541nm处有着较强的绿光发射,所以将在发光以及显示领域有潜在的应用前景。

Luminescence Properties of Ce3+ and Tb3+ ions Codoped Strontium Borate Phosphate Phosphors

The phosphors of 2SrO·0.25B₂O₃·0.75P₂O₅:RE³⁺ (RE=Ce,Tb)were synthesized by high temperature solid state reaction. The luminescence properties of Ce³⁺, Tb³⁺, the sensitization of Ce³⁺ to Tb³⁺and dynamics of them were studied. The results indicate that the brightness for the⁵D₄→⁷F₅ green emissions of Tb³⁺in the phosphor of Ce³⁺and Tb³⁺ co-doped 2SrO·0.25B₂O₃·0.75P₂O₅, corresponding to Ce³⁺excitation greatly increased in comparison with that in single Tb³⁺ doped samples. As the concentration of Tb³⁺varies from 1% to 8%, the energy transfer efficiency between Ce³⁺ and Tb³⁺ reaches to as high as 70%. The present results demonstrate that in the phosphor of Ce³⁺and Tb³⁺ co-doped 2SrO·0.25B₂O₃·0.75P₂O₅ efficient energy transfer exists. The Ce³⁺ and Tb³⁺ co-activated 2SrO·0.25B₂O₃·0.75P₂O₅ powders can possibly be applied as the newly developed green efficient phosphors in the field of lighting and display.