Complete Electrolytic Plastron Recovery in a Low Drag Superhydrophobic Surface

Abstract

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 a 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.