现场TEM成像揭示了金纳米颗粒中吸引力,排斥力和顺序吸引力-排斥力之间的动态相互作用
Abid Zulfiqar1, Mari Honkanen1,2, Nonappa1
1Faculty of Engineering and Natural Sciences, Tampere University, Tampere, FI-33720, Finland.
Small (Weinheim an der Bergstrasse, Germany)
|October 8, 2024
概括
电子束辐射可以导致金纳米粒子 (Au NPs) 排斥,而不仅仅是凝聚. 这项研究揭示了Au NPs中独特的吸引力-排斥行为,可以通过电子剂量和大小来控制.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 表面科学是一门学科.
背景情况:
- 对金属纳米粒子 (NP) 的电子束操纵提供了对它们的行为,结构变化和新兴性质的洞察.
- 虽然电子束诱导的NP凝聚越来越被理解,但排斥等现象仍未得到充分研究.
研究的目的:
- 在电子束辐射下研究金纳米粒子 (Au NPs) 之间的排斥和吸引现象.
- 探索NP大小和电子剂量率对粒子间相互作用和动态的影响.
主要方法:
- 利用现场传输电子显微镜 (TEM) 来实时成像纳米粒子相互作用.
- 采用小 (≈5.9 nm) 和大 (≈11.0 nm) 黄金纳米粒子 (Au NPs).
- 变化的电子剂量率,以观察动态的NP行为.
主要成果:
- 证明NP排斥在室温电子束辐射下与凝聚一样有利.
- 观察到Au NPs中独特的顺序吸引-排斥行为,取决于大小和电子剂量.
- 量化排斥率:低剂量率显示小AuNP在0.4nm/min时排斥,大AuNP在0.08nm/min时排斥.
- 发现大型Au NPs在高电子剂量速率下表现出最初的吸引力 (15分钟),随后是快速的排斥.
结论:
- 电子束辐射可以诱导金纳米粒子之间的吸引力和排斥力,挑战唯一的聚合焦点.
- 观察到的顺序吸引-排斥行为为控制粒子间距离提供了一个新的机制.
- 在不改变NP尺寸的情况下,这种可控制的粒子间距离操纵对先进的光子和等离子纳米设备具有前景.
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