Recent studies on sol–gel based corrosion protection of Cu—A review

This review discusses various sol–gel coatings for the corrosion protection of Cu. It is used in various industries, including automotive, electronics, oil/gas, and thermal–power plants, owing to its electrical/thermal conductivity, and mechanical ductility. However, Cu undergoes severe corrosion in aggressive chloride environments, causing considerable industrial losses. Sol–gel coatings for Cu metal protection are a preferred to other types of metallic coatings, because they are cost effectiveness, simple preparation methodology and eco-friendly. Sol–gel coatings compromise a produce an adhesive and compact layer that adheres to the metal surface and acts as a barrier, preventing the diffusion of aggressive Cl ions into the Cu metal and impeding corrosion. The synthesis, morphological studies, and corrosion protection methods of some advanced sol–gel based hybrid protective coatings are discussed in this review. Furthermore, the corrosion protection ability of these sol–gel coatings and their future development prospects are addressed. Graphical abstract