Scalable polydopamine@ZrO2/PVDF composite ink for corrosion protection of magnesium alloy

Two-dimensional (2D) materials have exhibited significant potential in the field of metal anticorrosion coatings. However, nanosheets with high electrical conductivity may promote “corrosion-enhancing activity,” thereby compromising the protective efficacy of the coating. In contrast, metal oxide nanosheets derived from layered compounds present a promising alternative due to their favorable properties. In this study, a composite ink for AZ31 magnesium alloy anticorrosion with blade coating method is fabricated by polydopamine (PDA)-coated ZrO 2 nanosheets/polyvinylidene fluoride (PVDF). The surface composition and microstructure of the resulting coating are systematically characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The anticorrosion properties of the composite coating are evaluated through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The electrochemical results demonstrate that the ZrO 2 @PDA/PVDF coating achieves a corrosion protection efficiency of 99.93 %, with a corrosion current density of 9.48 × 10 −8 A·cm −2 , which is three orders of magnitude lower than that of bare AZ31. This study provides a new insight into the scalable application of metal oxide nanosheets in metal anticorrosion coatings.