从超原子到等离子介导的磁循环二元化在合金属纳米粒子的演化跨越非金属到金属的极限
Juniper Foxley1, Thomas D Green2, Marcus A Tofanelli3
1Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States.
The journal of physical chemistry letters
|May 31, 2023
概括
这项研究使用磁圆二元化 (MCD) 谱学研究了黄金纳米集群. 结果显示,复杂的磁光特性随纳米集群大小而变化,为可调光学材料提供了潜力.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 合金属纳米集群表现出独特的电子和光学特性.
- 了解磁光吸收对于开发新材料至关重要.
- 黄金纳米集群的过渡从非金属到金属的政权随着尺寸的增加.
研究的目的:
- 为了检查金纳米集群的磁光吸收特性.
- 为了将这些特性与纳米集群大小和电子结构相关联.
- 探索可调光学材料的潜在应用.
主要方法:
- 采用了可变温度可变场磁圆二元化 (VTVH-MCD) 光谱法.
- 分析了不同的金纳米集群大小的光谱:Au25,Au144和Au459.
- 确定并分析了法拉第的A-术语和C-术语.
主要成果:
- 非金属Au25 ((SC8H9) 18) 显示MCD光谱由法拉第C-项主导,表明了对磁性.
- 金属 Au459 ((pMBA) 170 呈现出温度独立的 VTVH-MCD 光谱,其中法拉第 A 项占主导地位.
- 介质Au144 (((SC8H9) 60显示复杂的VTVH-MCD光谱,具有偏磁和混合过渡,并非来自等离子激发.
结论:
- 黄金纳米集团电子转换变得越来越复杂,因为尺寸接近金属尺度.
- 通过控制纳米集群大小和电子配置,可以调整磁光学特性.
- 这些发现为设计具有量身定制的磁光反应的体纳米结构开辟了道路.
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