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跳跃的纳米液滴可以跳跃
A Habenicht1, M Olapinski, F Burmeister
1Department of Physics, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.
Science (New York, N.Y.)
|September 24, 2005
概括
激光脉冲融化了平面黄金纳米结构,导致它们迅速收缩成球体. 这种快速的湿过程可以以高速速度将纳米颗粒从表面发射出来.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 激光物理 激光物理
背景情况:
- 纳米结构的制造通常涉及基板上的薄膜.
- 激光诱导的过程可以改变材料的特性和形态.
- 了解化纳米粒子的动态行为对于应用至关重要.
研究的目的:
- 研究激光化金纳米结构的动态行为.
- 分析露水和收缩过程.
- 确定纳米粒子脱离和速度的潜力.
主要方法:
- 用单个强烈的激光脉冲照明平面黄金纳米结构.
- 在惰性基板 (玻璃,石墨) 上观察结构变化.
- 在纳米秒内分析液体收缩和质量中心运动.
主要成果:
- 在黄金化值以上的激光流动引发了液态结构.
- 一个快速的潮湿过程导致在纳米秒内球形收缩.
- 收缩期间的惯性效应导致质量中心向上运动.
- 观察到滴滴的分离,100纳米半径的滴滴的速度高达10m/s.
结论:
- 激光诱导的融和湿提供了一条通往动态纳米粒子重塑的途径.
- 该过程可以导致纳米颗粒从基板中能量分离.
- 实现的高速度表明了纳米粒子操纵和沉积的潜力.
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