Effect of different acid anions on kinetics of the formation and dissolution behavior of anodic zirconium oxide

Effects of sulfuric acid (H2SO4), phosphoric acid (H3PO4), nitric acid (HNO3), and hydrochloric acid (HCl) on kinetics of the formation and dissolution behavior of zirconium oxide (ZrO2) were studied using the impedance, potential, and galvanostatic techniques. The oxide film did not form galvanostatically in 1 M HCl because of dissolution simultaneously with formation while the rate of formation in other acids decreased in the order: H2SO4 > H3PO4 > HNO3. Impedance and potential measurements reflected the same dissolution process, with the rate of formation decreasing in the order: HCl > HNO3 > H2PO4 > H2SO4. The theory of anodization was applied, and data were collected for reciprocal capacity, electrolytic parameters, and field strength. Activation energy during the oxide film formation was calculated as 4.99 kJ/mol. A general treatment was applied using three models under galvanostatic conditions.