Creation of a superhydrophobic surface from a sublimed smectic liquid crystal

Abstract

Dual-scale structures showing superhydrophobic characteristics have been fabricated using sublimable smectic liquid crystals (LCs). Here, toric focal conic domains (TFCDs) of smectic LCs were prepared on micron-sized square pillar patterns. And the layer by layer reconstruction of TFCDs under a thermal sublimation process was followed to form nano-scale hemi-cylinders. Based on this dual-scale roughness, the superhydrophobic surface was successfully created with a water contact angle (CA) of ∼150° and a low CA hysteresis of ∼9°. The resulting superhydrophobic surface is the first application using sublimable LCs, suggesting a new approach for potential applications in LC science and engineering.