Influence of nitrogen-fluorine co-doped graphene oxide on the corrosion resistance of epoxy low-zinc coatings

Developing high-performance, low-zinc epoxy coatings remains challenging. This study introduces fluorine-nitrogen co-doped graphene oxide into a low-zinc (40 wt%) epoxy coating to synergistically enhance its corrosion resistance. Systematic characterisation reveals that N doping repairs the carbon network while F doping forms semi-ionic C-F bonds, enhancing hydrophobicity and dispersion. The fluorine-nitrogen co-doped graphene oxide-based coating exhibited a contact angle of 114.2° and, after 28 days in 3.5 wt% NaCl, a low-frequency impedance of 6.621 × 10 8 Ω·cm 2 with a stable corrosion current density (10 −8 A·cm −2 ), significantly outperforming reference samples. This work demonstrates that F-N co-doping effectively balances conductivity and barrier properties, offering a novel strategy for durable anti-corrosion coatings.