A graphene spin coatings for cost-effective corrosion protection for the magnesium alloy AZ31

A graphene coating, prepared via spin coating on the Mg alloy AZ31, was characterized using Raman spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The Raman spectra indicated that the graphene spin coatings were uniform over the surface of AZ31. The SEM indicated the chemical composition of the graphene coating. The XPS analysis indicated that the carbon was mainly composed of conjugated double bonds. The corrosion behavior was evaluated from potentio-dynamic polarization curves and electrochemical impedance spectroscopy (EIS). The graphene coating decreased the corrosion rate of AZ31 by three orders of magnitude.