pH-Responsive Graphene Oxide-Based 2D/3D Composite for Enhancing Anti-Corrosion Properties of Epoxy Coating

Abstract

The functionalized graphene oxide (GO)-based composites as fillers added into organic coatings are desired for realizing the longstanding corrosion protection of carbon steel. Here, the pH-responsive two-dimensional/three-dimensional (2D/3D) GO-based composite (ZIF–90–AAP/GO) was developed by environmentally friendly corrosion inhibitor 4-aminoantipyrine (AAP) anchored on the in situ growth of zeolite imidazolate framework–90 (ZIF–90) on the GO surface (ZIF–90/GO) through the Schiff base reaction. The active filler (ZIF–90–AAP/GO) was incorporated into an epoxy coating (EP) to obtain a high-performance self-healing coating on the surface of carbon steel. ZIF–90–AAP can greatly improve dispersion and compatibility of GO in EP. The low-frequency impedance modulus of ZIF–90–AAP/GO–EP can still reach up to 1.35 × 1010 Ω⋅cm2 after 40 days, which is about three orders of magnitude higher than that of the EP containing GO (GO–EP) relying on its passive and active corrosion protection. Meanwhile, ZIF–90–AAP/GO–EP exhibits excellent self-healing performance. The self-healing rate of ZIF–90–AAP/GO changes from negative to positive after 24 h, which results from the effective corrosion inhibition activity of ZIF–90–AAP for carbon steel based on the pH-triggered controlled release of AAP. The developed pH-responsive 2D/3D GO-based composite coating is very attractive for the corrosion protection of carbon steel.

Study on the Effects of GO on the Microstructure and Wear Resistance of CuCrZr Plasma Cladding Coatings

“…Graphene oxide (GO), a derivative of graphene produced through oxidation, possesses a higher density and improved stability and machinability due to the introduction of oxygen atoms that form functional groups like carboxyl, hydroxyl, and epoxy groups. This modification facilitates the uniform dispersion of powders, enabling the preparation of alloy coatings with enhanced mechanical properties [16][17][18]. Graphene oxide (GO) possesses exceptional physical and chemical properties that can significantly enhance the mechanical strength, thermal and electrical conductivity, as well as corrosion resistance of materials.…”