强大的,高度发光的Au13超原子受到N-异环碳素的保护
Mina R Narouz1, Shinjiro Takano2, Paul A Lummis1
1Department of Chemistry , Queen's University , Chernoff Hall, Kingston , Ontario K7L 3N6 , Canada.
Journal of the American Chemical Society
|September 10, 2019
概括
由N-异环碳酸 (NHC) 稳定的新金超原子纳米集群表现出增强的光发光. 这些NHC-Au集群表现出高稳定性和广泛的能量差距,超过之前的配体保护的金纳米集群.
科学领域:
- 无机化学
- 纳米技术
- 材料科学
背景情况:
- 由于其独特的特性,金纳米集群对各种应用具有前景.
- 黄金纳米集群的稳定通常涉及可以影响其电子和光学特性的配体.
- N-异环碳素 (NHC) 为金属复合物提供强大的稳定性.
研究的目的:
- 通过N-异环碳素 (NHCs) 和化物稳定新型金超原子纳米集群的合成和特征.
- 研究这些新开发的NHC-Au纳米集群的结构,光学和电子特性.
- 将这些NHC稳定集群的性能与现有的配体保护的金纳米集群进行比较.
主要方法:
- 精确定义的NHC-Au-Cl复合物的合成.
- 减少前体复合物以形成金超原子纳米集群.
- 用X射线结晶学进行结构阐明.
- 光发光光谱测定量子产量
- 电子结构的密度功能理论 (DFT) 分析.
主要成果:
- 已经成功合成了具有icosahedral Au13核心的金超原子纳米集群.
- 集群由9个NHC和3个化物稳定,具有显著的CH-π和π-π相互作用.
- 观察到异常高的光发光量子产量,高达16.0%.
- DFT分析显示了一个8电子超原子配置,具有2 eV的HOMO-LUMO能量差距.
- 与素稳定黄金集群相比,表现出高稳定性.
结论:
- NHC连接物为金超原子纳米集群提供有效的稳定性,从而提高性能.
- 独特的结构特征和电子配置有助于卓越的光发光和稳定性.
- 这些NHC-Au纳米集群代表了联体保护黄金纳米集群领域的重大进步.
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