Graphene derivatives as reinforcement in coatings based on epoxy and silane for enhancing its corrosion resistance – a latest advances review

Corrosion is costly in many industrial segments, from aeronautics to civil engineering. Besides the socio-economic costs, structural failures, decreased product durability, and environmental and human health are increasingly considered parameters in the search for new, innovative, and eco-friendly solutions to replace toxic treatments (e.g., chromatization) to delay the corrosion process of metals and their alloys. Organic, inorganic, and organic-inorganic hybrid-based coatings attracted science's attention owing to their sustainability and corrosion resistance. Epoxy and silane-based coatings are explored as a promising replacement for the standard anti-corrosive treatments as they are corrosion-resistant materials with good adhesion in various metallic substrates. However, these films are still susceptible to corrosive media permeation due to silane and epoxy micro-pores and cracks. Therefore, nanoparticle incorporation is widely used to improve these coatings' corrosion resistance, making graphene derivatives a great candidate for the material's reinforcement as its planar structure and impermeability add a tortuous path for electrolyte transportation. Hence, this review summarizes the latest advances regarding graphene's nano-reinforcement effect in nano-coatings based on silane, epoxy, and their hybrids, focusing on these films' improved corrosion resistance.