Graphene-based anti-corrosive coating on steel for reinforced concrete infrastructure applications: Challenges and potential

Abstract

• State-of-the-art review of graphene coatings for infrastructure applications. • Critical comparison of monolithic, laminate, and nanocomposite graphene coatings. • Consideration of practical factors stability, scalability, cost, sustainability. • Nanocomposites have the strongest long-term anti-corrosion. • Graphene-based coating is promising for future research in steel rebar coating field. Steel corrosion has been a major perpetual issue of concern for durability and structural integrity of steel and reinforced concrete infrastructure. Polymeric, zinc-galvanic and chromate conversion coatings are commonly applied to protect typical steel materials such as structural steel, reinforcing steel bar (rebar), mild steel and light gauge steel used in infrastructure. Yet, due to physical integrity, long-term performance and environmental concerns, their applications have been limited. In recent years, graphene has garnered considerable attention in the field of anti-corrosive coatings and substantial progress has been achieved in the development of particular graphene-based monolithic (single/few-layer graphene and graphene oxides) as well as laminate and nanocomposite coatings. Despite considerable efforts dedicated towards fundamental research, the laboratory to industry transition of graphene-based anti-corrosive coatings remains challenging. To this end, this report reviews the state-of-the-art on graphene-based coating technology with application to steel surfaces and discusses, both, experimental studies and theoretical aspects. Specifically, this review presents (i) production of different forms of graphene-based materials and the coating process; (ii) corrosion resistance and anti-corrosive coating performance of graphene-coated steel materials, (iii) key potential areas and challenges pertaining to the application of graphene-based coating to structural steel and rebar; and (iv) potential future directions towards corrosion protection and smart coatings.