Anti-corrosion design of layered zirconium-based metal-organic frameworks (Zr-MOF) enhanced epoxy nanocomposite coatings

In this work, two-dimensional UiO-67 nanosheets are successfully modified on graphene oxide (GO). The synthesized GO@2D-UiO-67 composite not only exhibits the electrical insulation characteristics of Zr-MOF, but also leverages the passive barrier effect of its 2D layered structure to prepare a highly anticorrosive epoxy coating. Electrochemical measurements reveal that the impedance modulus of the GO@UiO-67/EP composite coating remain two orders of magnitude higher than that of the pure EP coating even after 28 days of immersion in 3.5 wt % NaCl solution. This good long-term anti-corrosion performance could derive from the enhanced crosslinking density of composite coating due to the incorporation of GO@UiO-67 nanosheets. Furthermore, the shielding effect of layered structure and the corrosion inhibition behavior of organic ligands are proved to improve the corrosion resistance properties of composite coating. This research fills the application void of two-dimensional Zr-MOF composites in resin coatings, as well as serves as a forward-looking initiative to enhance the long-term corrosion protection of epoxy resin coatings.