Static and dynamic behaviour of aqueous drops on thin lubricating fluid-coated slippery (LCS) surfaces

Abstract

Inspired by Nepenthes pitcher plants, lubricating fluid infused slippery (LIS) surfaces have recently gained tremendous attention from various research groups. We, alternatively, present lubricating fluid-coated slippery (LCS) surfaces based on smooth solid surfaces. The biggest advantage of LCS surfaces over LIS surfaces is that solid surfaces need not be rough or porous. We discuss that the surface energy of the underlying solid surfaces plays the most important role in preparing the LCS surfaces. Lubricating fluid-coated hydrophilic surfaces result in sinking aqueous drops due to the instability of the thin lubricating film. Additionally, stable and floating aqueous drops are observed on similar hydrophobic surfaces. We also observed that the presence of surface roughness enhances the stability and performance of LCS surfaces. Later we discuss various characteristics of LCS surfaces and its effects on the static and dynamic behaviour of aqueous drops on LCS surfaces.