Efficient and Cost-Effective Single-Step Thin Overlay Zinc Oxide Nanostructure for Enhanced Corrosion Protection of Galvanized Steel

We present a simple, direct, one-step method for obtaining a hydrophobic ZnO nanostructure coating to prevent zinc oxidation (white rust). The corrosion resistance of ZnO nanostructure-coated galvanized steel (GI) was studied using the well-known electrochemical impedance spectroscopy (EIS) technique in a 3.5 wt% aqueous NaCl electrolyte solution. Through the thermal decomposition of zinc acetate dihydrate, a thin film of ZnO nanostructure was grown on top of the GI substrate. All specimens were characterized using FESEM, EDS, and XRD following GI surface modification with ZnO nanostructures. The wettability of the nanostructure-modified GI surface was also investigated using the contact angle method. In a 3.5 wt% aqueous NaCl solution, the ZnO nanostructure coating was more resistant to corrosion than the neat GI substrate. In an aqueous corrosive electrolyte medium, we observed ZnO nanostructures forming a hydrophobic surface on a GI substrate. This hydrophobic thin film coating of ZnO nanostructures is an excellent alternative for protecting the surface of GI substrates; thus, it can eliminate toxic material based coatings on GI substrates.

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