A ZnO-based nanocomposite coating with ultra water repellent properties

In this paper a simple and low-cost approach for the elaboration of a superhydrophobic nanocomposite coating is reported. This method can be used for preparing self-cleaning superhydrophobic coatings on large areas for different kinds of substrates. The synergistic effect of the micro-nano-binary scale roughness was produced by a silicone rubber/ZnO/SiO2 composite. A high static contact angle of about 162° and low contact angle hysteresis of about 7.5° was obtained for the prepared superhydrophobic surface on which water droplets were observed to easily roll off and bounce. This type of coating showed exceptional stability against UV exposure, humidity and heating. Also, good stability was observed after immersion in different aqueous solution.