Directional oil sliding surfaces with hierarchical anisotropic groove microstructures

Abstract

A robust directional oil sliding surface is presented by utilizing re-entrant micro-groove arrays inspired from the microgrooves of rice leaf. The overhang micro-groove arrays are shown to provide two primary goals of "omniphobicty" and "anisotropic sliding" with DI water (γlv = 72.1 mN/m) as well as mineral oil (γlv = 28 mN/m) and conventional photoresist.

Keywords: anisotropic wetting; oil sliding surfaces; overhang structures; rice leaf.