Reinforced anticorrosion performance of waterborne epoxy coating with eco-friendly L-cysteine modified Ti3C2Tx MXene nanosheets

In this study, MXene (Ti3C2Tx) nanosheets were modified by an amino acid (L-Cysteine) to fabricate functionalized MXene (fMX) hybrid material. Results derived from FTIR, XRD, EDS and XPS confirm that L-Cysteine has succeeded in covalently functionalizing MXene's surface. Later, fMX was introduced into the waterborne epoxy (WEP) coating as fillers, and its anti-corrosion performance was studied through electrochemical impedance spectroscopy and potentiodynamic polarization tests. After being immersed in 3.5 wt% NaCl solution for 30 days, fMX/WEP still maintains a higher impedance modulus at lowest frequency (1.21 × 109 Ω·cm2) and a lower corrosion rate (7.95 × 10−6 mpy) compared to blank WEP. It is resulted from the well dispersion of fMX nanosheets in WEP matrix as well as the enhanced barrier properties offered by fMX. Our research provides a promising strategy for green modified MXene to improve the corrosion resistance of the coating.