Engineering MXenes (Ti3C2Tx) surface with TiO2 for enhancing anti-corrosion performance of coatings

Abstract MXenes (Ti3C2Tx), an emerging two-dimensional (2D) material, derived from MAX phases, may have outstanding corrosion resistance performance due to its sheet property. However, pristine Ti3C2Tx is inappropriate to be used directly as an anti-corrosion filler, owing to the existence of hydrophilic groups. Herein, few-layered Ti3C2Tx sheets were modified via TiO2. Then functional Ti3C2Tx (Ti3C2&TiO2) was introduced to the waterborne polyurethane (WPU) coating. Finally, the corrosion resistance of the prepared composite coating was studied in detail. The results revealed that containing 0.1 wt%Ti3C2&TiO2 composite coating has excellent corrosion resistant performance. After 28 days' immersion, the lowest frequency impedance of WPU/0.1%Ti3C2&TiO2 composite coating was 6.64 × 107 Ω cm2, which was higher than that of WPU coating (3.48 × 106 Ω cm2). After 110 days’ immersion, the lowest frequency impedance of WPU/0.1%Ti3C2&TiO2 composite coating was 1.75 × 106 Ω cm2. Furthermore, the results of Tafel curves demonstrated that the corrosion current and corrosion rate of WPU/0.1%Ti3C2&TiO2 composite coating were the lowest. That were 2.79 × 10−9 A/cm2 and 3.25 × 10−5 mm/year, respectively. In conclusion, this work extended the great application prospects of functional Ti3C2Tx sheets in the fields of anti-corrosion.