Electrodeposition and Corrosion Properties of Zn-V₂O₅ Composite Coatings

Composite coatings were obtained by electrochemical codeposition of V₂O₅ nanoparticles with zinc, from an additive free acid sulfate bath. The corrosion behavior of electrodeposited Zn and Zn-V₂O₅ composite coatings was investigated in 3.5% NaCl solution using polarization and electrochemical impedance spectroscopy (EIS). The decrease in I _corr values and an increase in R _ct values show the higher corrosion resistant nature of Zn-V₂O₅ coatings. The observed textural modifications of composite coatings are associated with the specific structural modification of Zn crystallites provoked by the adsorption-desorption phenomena occurring on the metal surface, induced by the presence of V₂O₅ nanoparticles. It has been observed that the presence of V₂O₅ nanoparticles favors the [1 0 2] and [1 1 2] texture of zinc matrix. Moreover, the codeposition of V₂O₅ nanoparticles with zinc was found to be favored at pH 3.5 and applied current density 4 A dm⁻². A considerable grain refinement of the deposit occurred due to incorporation of V₂O₅ nanoparticles and hence improved the preferred orientation of the zinc crystallites.