在任意度下确定纳米粒子的速率方程,并大幅增强非辐射转换
Jinhua Wu1,2, Zhang Liang1,2, Hao Sun2
1College of Integrated Circuits and Optoelectronic Chips, Shenzhen Technology University, Shenzhen, 518118, China.
Nanoscale
|June 3, 2025
概括
本研究在所有Er度中建立了基于Erbium (Er) 的NaYF4纳米粒子 (ENPs) 的速率方程. 它揭示了非辐射转换随着Er度的增加而增加,解释了高度缩的ENP中弱的上转换.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 量子光学是一种量子光学.
背景情况:
- 基于 (Er) 的NaYF4纳米粒子 (ENPs) 对成像和传感等应用至关重要.
- 欧洲近距离电网的现有速率方程 (REs) 仅限于低度的Er (~2%) 并仅关注上转换.
- 了解整个Er度范围内的过渡,包括向下转换,至关重要.
研究的目的:
- 确定整个 (Er) 度范围内的ENP的速率方程 (REs) 的系数.
- 调查不同ER级别的ENP中的上转换和下转换过程.
- 建立适用于任意 Er 度的 ENP 的综合模型.
主要方法:
- 系统地描述具有Er度为5%,50%,75%,100%的ENP.
- 可见和近红外辐射波段的校准.
- 曲线拟合以获得任意Er度下RE的参数值.
主要成果:
- 发现非辐射转换和能量转移过程随着Er.度的增加而增加四分之一.
- 从4I11/2到4I13/2的非辐射过渡随着Er度的增加而显著加速.
- 下转化在100%的Er度中最为突出,这解释了上转化效率的降低.
结论:
- 该研究提供了第一个在任意Er度下为ENP的速率方程.
- 已建立的RE可以为各种应用程序更好地设计和理解ENP.
- 这些发现澄清了Eer度与ENP上升转换效率之间的反向关系.
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