Lloyd Ben P, Bartlett Philip N, Wood Robert J K
National Centre for Advanced Tribology at Southampton (nCATS), University of Southampton, Southampton, SO17 1BJ, U.K.
Chemistry, University of Southampton, Southampton, SO17 1BJ, U.K.
ACS Omega. 2021 Jan 28;6(5):3483-3489. doi: 10.1021/acsomega.0c03466. eCollection 2021 Feb 9.
We present a superhydrophobic surface capable of recovering the lubricious gas layer known as the "plastron" from a fully wetted state underwater. It is shown that full plastron recovery is possible without a second layer of structural hierarchy, which is prone to irreversible wetting transitions. This allows us to use a cheap, fast, and potentially scalable method to fabricate the surface from silicone and carbon black in a molding process. We demonstrate plastron recovery from the fully wetted state and immediate plastron recovery after pressure-induced wetting transitions. The wetting state can be measured remotely and quickly by measuring the capacitance. The slip length is measured as ∼135 μm, agreeing well with the theory given the geometry of the surface. The ability of the surface to conform to small radii of curvature and withstand damage from loading is also demonstrated. The work presented here could allow superhydrophobic surfaces to reduce drag on ships and in pipes where the plastron would otherwise rapidly dissolve.
我们展示了一种超疏水表面，它能够在水下从完全湿润状态恢复被称为“气膜”的润滑气体层。结果表明，无需第二层结构层次就能实现气膜的完全恢复，而第二层结构层次容易发生不可逆的润湿转变。这使我们能够采用一种廉价、快速且具有潜在可扩展性的方法，通过模塑工艺用硅酮和炭黑制造该表面。我们展示了从完全湿润状态恢复气膜以及在压力诱导的润湿转变后立即恢复气膜的过程。通过测量电容可以远程快速测量润湿状态。测得的滑移长度约为135μm，与考虑表面几何形状的理论结果吻合良好。还展示了该表面适应小曲率半径并承受加载损伤的能力。本文所展示的工作可以使超疏水表面减少船舶和管道中的阻力，否则气膜会迅速溶解。
