Stability of Electrolyte Films on Structured Surfaces

Abstract

We investigate the stability of a thin film of liquid electrolyte on an electrically charged structured surface with a periodic array of gas-filled grooves. We derive a nonlinear evolution equation for the film thickness by taking into account the effects of structuring into our system of lubrication-type equations. We analyze how the introduction of structuring destabilizes the film by increasing either the Navier slip length or the length of the groove at the no-shear segments. We perform nonlinear simulations for the evolution of the film thickness to show that structuring decreases the rupture time with respect to a thin film on a solid surface.