Synergistic anti-corrosion and anti-wear of epoxy coating functionalized with inhibitor-loaded graphene oxide nanoribbons

Abstract

The synergy between corrosion protection and wear resistance is an effective strategy for the development of multifunctional coating to withstand complex working conditions. This study reports an epoxy resin coating filled with benzotriazole loaded metal-organic frameworks (BTA-MOFs) functionalized graphene oxide nanoribbons (GONR) that exhibit active anti-corrosion, act as a barrier to corrosive ion, and enhance wear resistance. The GONR@BTA-MOFs composite is synthesized through chemically etching multi-walled carbon nanotubes and subsequent electrostatic self-assembly corrosion inhibitors loaded MOFs onto the GONR. The composite demonstrates improved compatibility with epoxy resins compared to carbon nanotubes. The anti-corrosion performance of the composite coating is investigated using electrochemical impedance spectroscopy. After immersing in a 3.5 wt.% NaCl solution for 25 d, the alternating current impedance of the composite coating is three orders of magnitude higher than that of pure epoxy resin. Simultaneously, the controlled release of the corrosion inhibitor retards the deterioration of the coating after localized damage occurrence, which functions as active corrosion protection. The GONR@BTA-MOFs/EP composite coating exhibits the highest corrosion potential of -0.188 V and the lowest corrosion current of 3.162 × 10⁻⁹ A cm⁻²) in the Tafel test. Tribological studies reveal a reduction in the friction coefficient from 0.62 to 0.08 after incorporating GONR@BTA-MOFs in the coating, with the wear volume being seven times lower than that of pure epoxy resin. The excellent lubrication effect of the nanomaterials reduces the coefficient of friction of the coating, thereby improving the abrasion resistance of the coating. The synergy between the self-lubrication of the two-dimensional layered fillers and the corrosion resistance of the smart inhibitor containers suggests a promising strategy for enhancing the performance of epoxy resins under complex working conditions.