Sessile drop evaporation on (super)hydrophobic surfaces: Effect of low pressure on the contact line dynamics
Sessile drop evaporation on (super)hydrophobic surfaces: Effect of low pressure on the contact line dynamics
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DOI：
10.1016/j.colsurfa.2015.07.002
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发表时间：
2015-10
期刊：
影响因子：
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通讯作者：
I. Kiper;R. Fulcrand;C. Pirat;G. Simon;B. Stutz;S. Ramos
中科院分区：
文献类型：
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作者：
I. Kiper;R. Fulcrand;C. Pirat;G. Simon;B. Stutz;S. Ramos
在这篇文章中，我们实验研究了周围的压力范围在1 kPa和101 kPa之间的疏水和超疏水基底上的液滴的蒸发动力学的影响。这些表面，最初，由nanocoating的蚀刻和/或nonetched铝基板。液滴的蒸发被观察到发生在两个不同的制度：钉扎接触线（PCL）和移动接触线（MCL）。它们对液滴蒸发的全谱的贡献由润湿性质和压力值两者调制。结果表明，三线及其界面表现出显着的依赖于周围的压力，通过显着降低水接触角。压力对超疏水状态稳定性的影响也得到了证实。临界压力值通过实验确定（Ps ≤ 20 kPa）。在较低的压力下，Cassie-Baxter到Wenzel的转变发生，对于最低的压力（P≤ 5 kPa），这被证明是准瞬时的。微结构化表面的超高速在这样的条件下丧失。
In this article, we experimentally study the influence of the surrounding pressure ranging between 1 kPa and 101 kPa on the evaporation dynamics of drops on hydrophobic and superhydrophobic substrates. These surfaces were, initially, constructed by nanocoating of etched and/or nonetched aluminum substrates. The evaporation of droplet is observed to occur in two distinct regimes: pinned contact line (PCL) and moving contact line (MCL). Their contribution to the full spectrum of the drop evaporation is modulated by both wetting properties and pressure values. It is shown that the triple line and its interfaces exhibit a remarkable dependence on the surrounding pressure through a significant decrease in the water contact angle. The influence of the pressure on the stability of the superhydrophobic state is also evidenced as well. A critical pressure value is experimentally determined (Ps≈ 20 kPa). Under lower pressures a Cassie-Baxter to Wenzel transition occurs, which is shown to be quasi-instantaneous for the lowest pressures (P≤ 5 kPa). The superhydrophocity of micro-structured surfaces is lost in such conditions.