Influence of silanes on the wettability of anodized titanium

A facile method was adapted to make superhydrophobic (SHP) titanium in which a synergistic combination of surface roughness and surface chemistry was utilized. In the first step, titanium was mechanically polished and pickled followed by anodization. The next step was to dip coat the samples with silane solution and then were cured at 110 °C. Influence of different synthesis parameters such as silane concentration, number of dip coating and curing temperature on water contact angle (WCA) was studied and conditions were optimized to achieve a WCA of 150°. The wetting properties of the samples were elucidated using contact angle meter and the water just rolled off the modified titanium surface with a slight tilting. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the morphology and surface roughness of the silane coated titanium samples. Grazing incidence X-ray diffraction (GIXRD), energy dispersive spectroscopy (EDS), attenuated total reflection-infrared spectroscopy (ATR-IR) and X-ray photoelectron spectroscopy (XPS) were used to analyze the chemical composition of the coatings which confirmed the presence of silicon along with titanium and oxygen. Immersion studies in sea water and nitric acid medium for 15 days indicated the stability of the coatings with minimal variations in contact angle.