Analysis of electrochemical noise data in both time and frequency domains to evaluate the effect of ZnO nanopowder addition on the corrosion protection performance of epoxy coatings

Epoxy-ZnO nanocomposite coatings have been developed for corrosion protection of steel. Structural characterization of the prepared nanocomposites was performed using scanning electron microscopy (SEM). The anti-corrosive properties of the coatings were evaluated by electrochemical noise (EN). On the basis of the EN results in both time and frequency domains, the nanocomposite material with low ZnO concentration (0.1% wt.%) was found to be much superior in corrosion protection when tested in aqueous NaCl electrolyte. Finally, EIS measurements were carried out and the data fitted with suitable equivalent circuit. Resistance parameters obtained by both techniques were found to be in relatively good agreement.