ORALS

Graphene has triggered unprecedented research excitement for its exceptional characteristics. The most relevant properties of graphene as corrosion resistance barrier are its remarkable chemical inertness and impermeability and toughness, i.e., the requirements of an ideal surface barrier coating for corrosion resistance, thus, an interest in graphene coating as a disruptive approach to corrosion mitigation. However, the extent of corrosion resistance due to chemical vapour deposition (CVD) graphene coatings has been found to vary considerably in different studies. The author’s group demonstrated the ultra-thin graphene coatings developed on copper and nickel by CVD to improve corrosion resistance of the metals by two orders of magnitude in aggressive aqueous chloride environments. In contrast, other reports suggest the graphene coating to actually enhance corrosion rate of copper, particularly during extended exposures. Author’s group has investigated the reasons for such contrast in corrosion resistance due to graphene coating as reported by different researchers, and on the basis of the findings, they have succeeded in developing multilayer graphene coatings that conferred durable corrosion resistance to copper and nickel in the aggressive chloride environment. Corrosion and its mitigation costs dearly (any developed economy loses 3-4% of GDP due to corrosion, which translates to ~$250b to annual loss USA). In spite of traditional approaches of corrosion mitigation (e.g., use of corrosion resistance alloys such as stainless steels and polymeric coatings), loss of infrastructure due to corrosion continues to be a vexing problem. Therefore, it is technologically as well as commercially attractive to explore graphene coating as a disruptive approach to durable corrosion mitigation. However, developing graphene coating on the most common engineering alloy, mild steel by CVD is a non-trivial challenge. The presentation will discuss the challenges, and their successful circumvention that enabled graphene coatings on mild steel, and presents results demonstrating durable and remarkable corrosion resistance of graphene-coated mild steel.