Xu Muchen, Sun Guangyi, Kim Chang-Jin
Mechanical and Aerospace Engineering Department, University of California at Los Angeles (UCLA), Los Angeles, California 90095, USA.
Phys Rev Lett. 2014 Sep 26;113(13):136103. doi: 10.1103/PhysRevLett.113.136103. Epub 2014 Sep 25.
Submerged superhydrophobic (SHPo) surfaces are well known to transition from the dewetted to wetted state over time. Here, a theoretical model is applied to describe the depletion of trapped air in a simple trench and rearranged to prescribe the conditions for infinite lifetime. By fabricating a microscale trench in a transparent hydrophobic material, we directly observe the air depletion process and verify the model. The study leads to the demonstration of infinite lifetime (>50 days) of air pockets on engineered microstructured surfaces under water for the first time. Environmental fluctuations are identified as the main factor behind the lack of a long-term underwater SHPo state to date.
众所周知，浸没的超疏水（SHPo）表面会随着时间从去湿状态转变为湿润状态。在此，应用一个理论模型来描述简单沟槽中捕获空气的消耗情况，并重新整理以规定无限寿命的条件。通过在透明疏水材料中制造一个微尺度沟槽，我们直接观察到空气消耗过程并验证了该模型。该研究首次证明了工程微结构表面上的气穴在水下具有无限寿命（>50天）。环境波动被确定为迄今为止缺乏长期水下SHPo状态的主要因素。
