Influence of the electrodeposition current regime on the corrosion resistance of Zn–CeO2 nanocomposite coatings

• Zn–CeO2 samples were obtained via direct current and pulse current electrodeposition.
• Composite Zn–CeO2 coatings are more resistant to generalized corrosion than Zn coating.
• GDOES analysis shows the presence of ceria nanoparticles in the depth of the coating.
• Use of pulsed current, together with the presence of nanoparticles, offers compact deposits.
• The presence of nanoparticles in the coating increases microhardness.

The present work aims at studying the influence of the current regime on the electrodeposition of zinc–ceria composite coatings obtained from a chloride based electrolyte, by using both direct and pulse current electrodeposition techniques. The microstructure, microhardness, composition profile and the corrosion parameters of the samples were evaluated via SEM, GDOES, microhardness tests and polarization curves, respectively. Pure zinc samples obtained under the same experimental conditions were used as a reference. The addition of CeO2 nanoparticles leads to finer grained deposits, with better corrosion resistant properties. The study also revealed that a pulsed-current regime is preferable to a direct-current approach of the electro-co-deposition process, leading to coatings with better anti-corrosion properties.