在CaF2:Tb3+中,Ce3+离子兴奋剂是否表现出比CeF3:Tb3+更多的发光?
Kedukhro Khupfu1,2, Medemmeren Longchar1, Watisenla Sangtam1,3
1Department of Physics, School of Sciences, Nagaland University, Lumami 798627, India. ssnaorem@nagalanduniversity.ac.in.
Dalton transactions (Cambridge, England : 2003)
|November 24, 2025
概括
与 (Ce3+) 和 (Tb3+) 合的化 (CaF2) 与三化 (CeF3) 相比,具有更高的发光强度. 由于其较大的带隙,CaF2被证明是Tb3+发光的更有效的主体材料.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 发光和光谱学 发光和光谱学
背景情况:
- 研究稀土合材料的发光特性对于开发先进的光学设备至关重要.
- 三化物 (CeF3) 和化物 (CaF2) 都是已知的化物离子的宿主,表现出低声子振动.
- 与CeF3相比,CaF2具有更大的带隙,从理论上来说,这表明合兰化离子的发光性能更好.
研究的目的:
- 通过实验来确定为什么CaF2:Ce3+中的Tb3+兴奋剂比CeF3:Tb3+产生更高的发光强度.
- 为了分析CaF2:Tb3+在Ce3+过度兴奋剂后的结构和发光变化.
- 为了比较CaF2和CeF3宿主中的Tb3+的发光特性和衰变动态.
主要方法:
- 使用时间分辨率发光光谱法来测量衰变寿命.
- 使用X射线衍射 (XRD) 和传输电子显微镜 (TEM) 进行晶体结构分析.
- 对化纳米晶体进行了发光强度和量子产量 (QY) 测量.
主要成果:
- 与CeF3:Tb3+相比,Tb3+离子在CaF2:Ce3+-Tb3+中表现出较长的衰变寿命,这证实了CaF2是优越的主体.
- 使用CaF2:Tb3+与Ce3+ (≥15at.%) 的过量注导致二次CeF3阶段的形成和Tb3+发光强度的下降.
- 在CaF2中,Ce3+-Tb3+的发光量子产量 (∼44%) 显著高于CeF3 (∼28%).
结论:
- CaF2是Tb3+发光的更有效的宿主材料,而不是CeF3,这是由于其更大的带隙.
- 从Ce3+到Tb3+的能量转移在两个宿主中都发生,但高Ce3+度的CaF2中的相分离会影响发光.
- 这项研究为优化发光纳米材料的宿主-辅助剂相互作用提供了关键的见解.
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