水滴在具有化学梯度的表面上的定向连续反弹行为
Yue Zhang1, Ao Gong2, Tao Wang1
1College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, PR China.
Langmuir : the ACS journal of surfaces and colloids
|February 25, 2025
概括
研究人员创建了一个具有化学梯度的表面,使液滴能够多次在方向上反弹,实现长距离运动. 这种"滴滴床"现象为控制滴滴运动提供了新的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 流体动力学 流体动力学
背景情况:
- 控制表面上的液滴行为对于各种应用至关重要.
- 现有的滴滴操纵方法在实现定向,重复反弹方面是有限的.
研究的目的:
- 为了设计一种能够诱导液滴方向多重反弹的表面.
- 为了研究连续反弹行为背后的机制.
主要方法:
- 制造具有精确控制的化学/湿梯度的Ti-6Al-4V基板.
- 利用蒸汽沉积来分配低表面能量的功能组.
- 分析滴滴粘附力,以量化湿度变化.
主要成果:
- 在工程表面上实现了2.5° mm-1的湿度梯度.
- 观察到水滴反复撞击并沿梯度反弹多达8次.
- 最大反弹高度和水平跳跃距离分别达到8.36毫米和10.19毫米.
结论:
- 在化学分级的表面上证明了滴滴的方向多重反弹.
- 阐明了控制"滴滴床"效应的能量和力机制.
- 这为精确操纵滴滴运动提供了一种新的策略.
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