Engineering the geometry of stripe-patterned surfaces towards efficient wettability switching

TL;DR

This paper investigates how the geometry of stripe-patterned surfaces influences their wettability switching capabilities, combining systems analysis and simulations to understand energy barriers between different wetting states.

Contribution

It introduces a systematic study of the relationship between stripe geometry and wettability transitions using mesoscopic simulations and energy barrier analysis.

Findings

Energy barriers depend on stripe geometry

Stable and unstable wetting states are characterized

Wettability switching can be optimized through pattern design

Abstract

The ability to control wettability is important for a wide range of technological applications in which precise microfluidic handling is required. It is known that predesigned roughness at a micro- or nano- scale enhances the wetting properties of solid materials giving rise to super-hydrophobic or super-hydrophilic behavior. In this work, we study the dependence of the apparent wettability of a stripe-patterned solid surface on the stripe geometry, utilizing systems level analysis and mesoscopic Lattice-Boltzmann (LB) simulations. Through the computation of both stable and unstable states we are able to determine the energy barriers separating distinct metastable wetting states that correspond to the well-known Cassie and Wenzel states. This way the energy cost for inducing certain wetting transitions is computed and its dependence on geometric features of the surface pattern is explored.