由于原子精确金纳米集群的氧化状态的可逆变化导致的两光子吸收的调制
Patryk Obstarczyk1, Julia Osmolska1, Martina Perić Bakulić2
1Institute of Advanced Materials, Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland.
The journal of physical chemistry letters
|March 12, 2026
概括
我们证明,黄金纳米集群的可逆氧化显著调节它们的非线性光学特性. 这种氧化状态的变化增强了两光子的吸收和切换吸收行为,为纳米集群的光学功能提供了新的控制.
科学领域:
- 纳米技术 纳米技术
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 原子精确的纳米集群提供可调节的光学特性.
- 有兴趣控制一个光子和两个光子的吸收.
- 外部刺激对非线性光学 (NLO) 属性的调制在纳米集群中还没有得到充分的研究.
研究的目的:
- 为了研究氧化-减氧过程对黄金纳米集群的NLO特性的影响.
- 通过氧化还原反应探索金纳米集群中二光子吸收 (TPA) 的调制.
- 建立电子结构和纳米集群的NLO响应之间的联系.
主要方法:
- 实验合成和金纳米集群的特征.
- 对一光子和两光子吸收的光谱测量.
- 密度函数理论 (DFT) 计算,以了解电子结构和光学特性.
- 研究[Au25(SR) 18) - - 的氧化还原诱导转化.
主要成果:
- [Au25(SR) 18) - 的可逆氧化到其中性形式导致光学光谱的显著变化.
- 在氧化后,在825-1150nm范围内的两光子吸收截面被增强了多达2倍.
- 在825nm以下观察到和吸收和两光子吸收之间的切换.
- 据DFT的计算表明, counterions 可以影响 TPA 的横截面.
结论:
- 氧化减氧过程是黄金纳米集群中NLO属性的有效调节者.
- 即使是纳米集群中微妙的电子变化也会导致NLO行为的明显变化.
- 这项工作为基于纳米集群的刺激响应NLO材料的设计打开了道路.
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