A high-performance waterborne polymeric composite coating with long-term anti-corrosive property based on phosphorylation of chitosan-functionalized Ti3C2Tx MXene

As a newly discovered two-dimensional (2D) material, MXene has attracted much attention because of its fascinating physicochemical properties. However, the issue of agglomeration has limited its application in anti-corrosive polymeric coatings. Herein, a novel nanofiller, phosphoric acid-modified chitosan (mCS)-functionalized MXene (fMX), has been successfully constructed and used to endow waterborne epoxy (WEP) coatings with brilliant corrosive resistance. Electrochemical results demonstrate that the |Z0.01 Hz| value for 0.2 wt% fMX/WEP composite coating (4.73 × 107 Ω cm2) is more than two orders of magnitude higher than that of the blank WEP (2.09 × 105 Ω cm2) and the corrosion current density value of 0.2 wt% fMX/WEP maintains above 5.44 × 10−9 A/cm2 after soaking in 3.5 wt% NaCl solution for 50 days. It is nearly two orders lower than that of blank WEP (5.23 × 10−7 A/cm2). Thus, this novel mCS-functionalized MXene can serve as an effective composite nanofiller for preparing MXene-based high-performance anti-corrosive coatings.Graphical abstractPhosphorylated chitosan-functionalized MXene (fMX)-based polymeric composite coatings have excellent long-term anti-corrosive property.