Making superhydrophobic building materials: static and dynamic behavior of nanostructured surfaces. INVITED

Wettability is a fundamental property of a solid surface, playing an important role in different industrial sectors; among building materials, super-hydrophobic surfaces, presenting a CA with water higher than 150°, exhibit enhanced self-cleaning attitude. Special wettability of surfaces can be achieved by means of chemical and microstructural modification at nano-scale: a functional top layer made up of ceramic oxides, with a thickness in the 200-300 nm range, can be deposited by easily available techniques, providing high repellence to water. Adequate nano-structured patterns need to be generated by thermal processing and introduction of low energy elements. By this way, static contact angle can reach values as high as 170°, also involving excellent dewetting phenomena, as certified by the very low hysteresis of advancing (?A) and receding (?B) angles. Coatings show a good mechanical resistance so that they can bring great convenience for different kind of materials.