Long-lasting anti-corrosion of superhydrophobic coating by synergistic modification of graphene oxide with polydopamine and cerium oxide

Superhydrophobic coatings have broad application prospects in construction and building materials due to their unique water-repellency. However, the practical application of these coatings is limited by their fragile surface microstructure. To overcome this limitation, in this work, a long-lasting anti-corrosion superhydrophobic coating was prepared on aluminum alloy using a straightforward spraying method. Graphene oxide (GO) was loaded with cerium oxide (CeO2), an inorganic corrosion inhibitor, and polydopamine (PDA) was used to improve the dispersion of GO. The strong adhesion ability of PDA greatly enhanced the mechanical properties of the superhydrophobic coating, resulting in a grade 5B adhesion. The inorganic corrosion inhibitor CeO2 not only can effectively fill the defects inside the organic coating but also can release cerium ions to form insoluble precipitates to prevent further corrosion. Through the synergistic effect of the robust superhydrophobic surface and corrosion inhibitors, the impedance still reaches 107 Ω·cm2 after 27 days of immersion, indicating that the coating has long-lasting anti-corrosion ability. This simple method of preparing robust anti-corrosion coatings provides an effective strategy for the practical application of superhydrophobic coatings.