Sequentially Bridged Graphene Sheets for High-Performance Anticorrosion

Graphene has been widely studied in metal protection due to its complete impermeability and ultrathin properties. However, it is still a huge challenge to fully use the unparalleled features to design and construct graphene-based coatings with long-term anticorrosion properties. Herein, a facile and scalable approach to design an ultrathin bioinspired graphene-based (B–G–WEP) composite coating through sequential bridging of interfacial interactions and ordered graphene layers, is described. The combination of covalent bonding and π–π stacking greatly increases the graphene sheet ordered alignment and compatibility with epoxy matrix. This optimizes physical barrier effect, penetration resistance to sea water, and resistance to localized galvanic corrosion deterioration. The resultant B–G–WEP coating has a 190-times reduced corrosion rate as well as a three-orders increased impedance modulus, and keeps a high protection efficiency of 99.5% after 60 days of immersion tests. Furthermore, the coating damage function and coating damage index also decline by 2.8- and 10.7-fold, respectively. This work provides overall consideration to facile, scalable, practical, high barrier and anticorrosion properties, showing great potential applications for high-efficiency and durable metal protection.