Corrosion Inhibition of Zinc by Aqueous Vanadate Species

Abstract

This study presents a characterization of the degree and mechanism of corrosion inhibition of Zn by vanadate inhibitors. A combination of open circuit potential measurements, anodic and cathodic polarization, and Raman spectroscopy were used to compare corrosion inhibition of Zn exposed to or pre-treated with a dilute ∼pH 6.3 NaVO3+NaCl solution, which likely contained predominantly tetrahedrally coordinated vanadate species, relative to controls. The presence of vanadate caused a decrease in corrosion current density of up to two orders of magnitude due to overall mixed anodic and cathodic inhibition associated with the formation and/or stabilization of adherent surface films.