Facile fabrication of a low-cost, room-temperature curable superhydrophobic coating with excellent stability

SiO2 based superhydrophobic coating has been widely studied as a promising material to extend the service life of various materials. However, the simple preparation of a robust superhydrophobic coatings with room temperature curing capability at low cost is still a challenge in this field. In this work, the fluorinated SiO2 is made from inexpensive industrial water glass by a simple sol-gel method, and the coating is produced by a two-step brushing process and cured at room temperature. The stability of superhydrophobic coatings was verified by wear resistance, chemical stability, and high temperature resistance. Under the ideal preparation conditions obtained by hydrophobic characterizations, the contact angle can be as high as 158.9°, the slide angle is only 3.2°, and it has outstanding self-cleaning properties. The SiO2-EP superhydrophobic coatings notably possess exceptional wear resistance in both smooth glass and rough cement mortar surfaces. Especially on the glass, it can maintain to be superhydrophobic after being worn 50 cycles with 100 g load and 35 cycles with 200 g load on 600-mesh sandpaper. In addition, it maintains excellent superhydrophobic properties even under high temperatures of 300 °C and extreme acid and alkaline corrosive environments. This offers a broad range of application prospects for the application of superhydrophobic coatings for use on various substrates and in extreme environments.