Synthesis of Zn-Ceria Nanocomposite Coatings from Particle-Free Aqueous Bath in a one Electrodeposition Step Process

Zinc-cerium/hydroxides nanocomposite films have been successfully synthesized through a galvanostatic electrodeposition process from a monophasic chlorides bath. Bath composition has been selected in order to avoid zinc hydroxides precipitation thanks to zinc complexation by ammonia and favor cerium hydroxides precipitation. The codeposition of cerium based oxide during the electrogrowth of the zinc coating was investigated using SEM/EDX, and cerium based oxide nanoparticles were detected preferentially adsorbed at the edge of the zinc hexagonal platelets. Incorporation of the cerium based oxide particles does not affect the microstructure of the zinc coatings. The investigation of the corrosion properties reveals an important improvement of the corrosion resistance of the zinc nanocomposite coatings in NaCl saline solution. The evolution of the corrosion properties was correlated to the nature of the cerium base oxide nanoparticles incorporated inside the zinc coating. The obtained nanocomposite film exhibits really promising behaviour regarding corrosion in saline solution due to zinc corrosion products stabilization by cerium hydroxide.