Facile Preparation of a Robust Superhydrophobic SiO2/Epoxy Composite Coating with Favorable Corrosion and Scale Inhibition Performance

Abstract

Superhydrophobic surfaces with good water repellency are widely studied, but their complex preparation process and poor durability limit their practical application. Herein, a simple and environmentally friendly method to prepare a robust superhydrophobic coating is proposed and its application in the field of corrosion prevention and scale inhibition is explored. Environmentally friendly and low-cost SiO₂ nanoparticles modified by octadecyl trimethoxysilane (ODMS) are mixed with epoxy resin and sprayed onto the surface of metal substrates. The prepared ODMS–SiO₂/epoxy resin composite coating has a water contact angle (WCA) of 161.5°, exhibiting excellent superhydrophobicity. In addition, the prepared coating maintains the original microstructure and good superhydrophobicity (WCA is 155°) after 30 cycles of wear test under 200 g load, showing excellent mechanical stability. The inherent superhydrophobic property also endows the coating with excellent corrosion and scale inhibition. The impedance of the composite coating is two orders of magnitude higher than that of the pure epoxy coating. The scaling amount of superhydrophobic composite coating in 24 h is 47% of that of epoxy resin coating. This work provides a new strategy for constructing multifunctional superhydrophobic coatings with excellent mechanical stability, corrosion resistance, and scale inhibition.