Preparation and corrosion behavior of layered double hydroxides-graphene oxide composite coatings modified by sodium dodecylbenzene sulfonate on the surface of AZ31 Mg alloy

Abstract

Layered double hydroxides (LDHs) are a class of two-dimensional anionic clays with adjustable structure, which have certain corrosion resistance. However, smooth growth path of LDHs nanosheets perpendicular to the substrate limits its application in the field of corrosion. Graphene oxide (GO) possess a high specific surface area and barrier properties, which provides a promising method for further improving the corrosion resistance of LDHs. In this work, we prepared three different concentrations of sodium dodecylbenzene sulfonate (SDBS) modified GO (GO:SDBS concentration ratio = 1:1, 1:2, 1:3), and present MgAlCe-LDHs@GO-SDBS composite coatings by one-step hydrothermal method with well-zigzag morphology and good corrosion resistance. GO-SDBS was successfully incorporated in the layered double hydroxide (LDHs), the corrosion current density of the MgAlCe-LDHs@GO-S₂ coatings was 1.60 × 10⁻⁸ A cm⁻², which was lower than other coatings. This one-step growth of MgAlCe-LDHs@GO-S method has potential applications in manufacture of anti-corrosion protection coatings.