在新的上转换CdSe/NaYF4:Yb,Er纳米 heterostructures中的近红外光响应
Chenglin Yan1, Afshin Dadvand, Federico Rosei
1Department of Chemistry and Center for Self-Assembled Chemical Structures, McGill University, 801 Sherbrooke Street West, Montréal, QC, Canada H3A 2K6.
Journal of the American Chemical Society
|June 12, 2010
概括
我们合成了新的纳米结构,结合了化 (NaYF4) 纳米晶和化 (CdSe) 量子点. 这种独特的组合使高效的上转换和能量转移成为可能,从而在近红外光下增强光导性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 量子点就是量子点.
背景情况:
- 添加兰化物的纳米晶体具有独特的光学特性.
- 量子点 (QD) 是具有可调节光学特性的半导体纳米粒子.
- 纳米 heterostructures 结合不同的纳米材料,以实现协同效应.
研究的目的:
- 为了合成和表征新型纳米结构的胺合NaYF4纳米晶体和CdSe量子点.
- 为了研究组件之间的能量传递机制.
- 为了评估产生的薄膜的光电子特性.
主要方法:
- 树突式NaYF4:Yb,Er纳米晶体的合成.
- 用CdSe量子点对NaYF4纳米晶体进行装饰.
- 光学和光导性能的表征.
主要成果:
- 成功合成了纳米异构结构,其中NaYF4:Yb,Er和CdSe之间具有强烈的合.
- 观测靠近红外光子的高效上升转换的兰坦化纳米晶体.
- 从NaYF4到CdSe的能量转移的演示,导致特有的CdSe排放.
- 在980nm辐射后,薄膜中显著的光导性.
结论:
- 合成的纳米异构结构表现出高效的能量转移和上转换特性.
- 这些材料显示出在光电子和光子学中的应用潜力.
- 该研究强调了整合化纳米晶体与量子点的好处,以增强功能.
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