A simple, rapid and single step method for fabricating superhydrophobic titanium surfaces with improved water bouncing and self cleaning properties

We report a simple, rapid, inexpensive and eco-friendly method for fabricating super hydrophobic (SHP) titanium surface using ethanolic solution of myristic acid and HCl through simultaneous anodization and adsorption. The coating performance is optimized by varying the anodization potential, acidic concentration and anodization duration. The prepared superhydrophobic surfaces are characterized using water contact angle (WCA), Fourier transform infrared (FTIR) spectroscopy, Laser Raman Spectroscopy (LRS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX). At an optimal anodization potential, the coated surface is found to be densely populated with hierarchical micro-nanoclusters of titanium dioxide adsorbed with myristic acid, exhibiting a maximum WCA of 176.3°±1° with a sliding angle of 1°. SHP surface showed surface features with layered ridges decorated with submicron sized aggregates. The liquid-air area fraction on the prepared SHP surface is ~0.97, with an asperity slope ψ > 71°. SHP surface exposed to microbial cultures for 48 h showed 50% reduction in bacterial adhesion. Bouncing dirt removal and bouncing of drops suggest better cleaning efficacy and excellent water repellency of the SHP surface. The fast fabrication, excellent anti biofouling, chemical and mechanical stability of the SHP coating offer interesting applications, and also opens up new ways for creating stable superhydrophobic titanium surfaces with excellent self cleaning characteristics.