Air-Stable Titanium Carbide MXene Nanosheets for Corrosion Protection

MXene materials have drawn extensive scientific interest in catalysis, batteries, purification, and electromagnetic interference shielding fields; however, their anticorrosion performance is rarely explored mainly because MXene nanosheets are prone to be oxidized under ambient conditions. Herein, we prepared oxidation-resistant and highly stable titanium carbide (Ti3C2Tx) MXene sheets through noncovalent functionalization between MXene and an ionic liquid (IL). The resultant IL@MXene nanosheets were used as a smart barrier enhancer of waterborne epoxy (WEP) to improve the anticorrosion performance of coatings. The impedance modulus of the IL@MXene–WEP coatings with a thickness of 13 μm increased by 1–2 orders of magnitude compared to that of the neat WEP coating, which was supported by potentiodynamic polarization curves and electrochemical impedance spectroscopy measurements. The morphologies of steels protected by the IL@MXene–WEP coatings exhibited less corrosion than the neat WEP, suggesting a satisfactory anticorrosion performance enhancement by the coating. Furthermore, the self-healing properties of the IL@MXene–WEP coating were confirmed using the scanning vibrating electrode technique. Its enhanced protection performance was attributed to the synergistic effects of the exceptional barrier property endowed by well-dispersed MXene nanosheets and the self-repairing property caused by IL passive films. Our work provides a strategy for the design and preparation of MXene smart anticorrosion coatings.