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

Journal Article · Fri May 01 04:00:00 EDT 1998 · Corrosion

DOI:https://doi.org/10.5006/1.3284862· OSTI ID:669822

El-Mahdy, G A ^[1]; Mahmoud, S S ^[2]

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1. Helwan Univ., Cairo (Egypt). Chemistry Dept.
2. Ain-Shams Univ., Cairo (Egypt)

Effects of sulfuric acid (H{sub 2}SO{sub 4}), phosphoric acid (H{sub 3}PO{sub 4}), nitric acid (HNO{sub 3}), and hydrochloric acid (HCl) on kinetics of the formation and dissolution behavior of zirconium oxide (ZrO{sub 2}) 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: H{sub 2}SO{sub 4} > H{sub 3}PO{sub 4} < HNO{sub 3}. Impedance and potential measurements reflected the same dissolution process, with the rate of formation decreasing in the order: HCl > HNO{sub 3} > H{sub 3}PO{sub 4} > H{sub 2}SO{sub 4}. 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.

• Sponsoring Organization: USDOE
• OSTI ID: 669822
• Journal Information: Corrosion, Journal Name: Corrosion Journal Issue: 5 Vol. 54; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTIVATION ENERGY
ANIONS
ANODIZATION
DISSOLUTION
FILMS
IMPEDANCE
INORGANIC ACIDS
KINETICS
OXIDATION
ZIRCONIUM