Cataphoretic deposition of an epoxy coating with the incorporation of Ti3C2Tx@Mg-Al layered double hydroxide for long-term active corrosion protection effect

Abstract

Epoxy composite coating with active corrosion inhibition property was prepared through cathodic electrophoretic deposition with the incorporation of Ti3C2Tx@Mg-Al layered double hydroxides (LDH) hybrid material. Hydrothermal method was adopted to synthesize molybdate (MoO42−)-intercalated MgAl LDH, which was self-assembled on the surface of Ti3C2Tx MXene through electrostatic interaction to improve the zeta potential of the Ti3C2Tx surface to positive value. Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscope, scanning electron microscope, X-ray photoelectron spectroscopy, zeta (ζ) potentials test and uv-vis spectroscopic analysis results showed that MgAl LDH and Ti3C2Tx@Mg-Al LDH were successfully prepared and Ti3C2Tx@Mg-Al LDH had ion exchange property. The prepared LDH and Ti3C2Tx@Mg-Al LDH were added to electrophoretic paint as anti-corrosive additives. After deposition process of 150 V for 2 min on the P110 steel surface, composite coatings had thicknesses of ~110 μm. Electrophoretic deposition has advantages in controlling coating thickness than traditional spray method. Moreover, Ti3C2Tx@Mg-Al LDH additive endowed composite coating with active corrosion inhibition capacity through ions exchange property between corrosive medium Cl− and MoO42− in the MgAl LDH interlayer. Electrochemical impedance spectroscopy (EIS) test results showed that Ti3C2Tx@Mg-Al LDH/epoxy coating exhibited outstanding corrosion protection property. This research provides a new way of using Ti3C2Tx MXene in the cathodic electrophoretic paint to prepare active anti-corrosive coating.