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Current Analytical Chemistry


ISSN (Print): 1573-4110
ISSN (Online): 1875-6727

Research Article

Cyclic Voltammetry as an Electroanalytical Tool for Analysing the Reaction Mechanisms of Copper in Chloride Solution Containing Different Azole Compounds

Author(s): Matjaž Finšgar*, Klodian Xhanari* and Helena O. Ćurković

Volume 16, Issue 4, 2020

Page: [465 - 474] Pages: 10

DOI: 10.2174/1573411014666180704114202

Price: $65


Background: Cyclic voltammetry is widely employed in electroanalytical studies because it provides fast information about the redox potentials of the electroactive species and the influence of the medium on the redox processes. Azole compounds have been found to be effective corrosion inhibitors for copper in chloride-containing solutions. The aim of this work was to investigate in detail the influence of the addition of various azole compounds on the oxidation mechanism of copper in chloride-containing solutions, using cyclic voltammetry.

Methods: The influence of thirteen azole compounds, at three different concentrations on the electrochemical/ chemical reactions of pure copper immersed in 3 wt.% NaCl solution was studied using cyclic voltammetry at different scan rates. The change of the peak current and potential with the scan rate were investigated. The possible linearity was compared with the theoretically derived mechanism. The possible reaction mechanisms were discussed based on the linearity of these parameters (peak current and potential) with the scan rate compared to theoretically derived models.

Results: Both the peak current and peak potential of the copper samples immersed in chloridecontaining solutions with additions of the majority of azole compounds showed linearity with the square root of the scan rate, suggesting that copper follows the Müller-Calandra passivation model. The same behavior was also found for copper in chloride-containing solutions without additions of azole compounds. A linear variation of the peak potential with the natural logarithm of the scan rate and linear variation of the peak potential with the square root of the scan rate was observed for the copper samples immersed in chloride-containing solutions with the addition of 10 mM of 2-mercapto-1- methylimidazole, imidazole, or 2-aminobenzimidazole. This suggests that copper follows irreversible redox reactions under a diffusion controlled process. No other linear relations of the peak current and peak potential with the scan rate were found.

Conclusion: Copper oxidation in chloride-containing solutions is controlled by passivation (following the Müller-Calandra passivation model) upon the addition of the majority of the selected azoles. In the minority of cases, irreversible redox reactions that follow a diffusion-controlled process were identified. None of the systems followed an adsorption-controlled process. Moreover, none of the tested systems underwent reversible redox reactions that followed a diffusion controlled process.

Keywords: Azole compounds, copper, cyclic voltammetry, electroanalysis, reaction mechanisms, redox processes.

Graphical Abstract
Wang, J. Analytical Electrochemistry, 3rd ed; John Wiley & Sons, Inc.: Hoboken, New Jersey, 2006.
Chan, H.T.H.; Kätelhön, E.; Compton, R.G. Voltammetry using multiple cycles: Porous electrodes. J. Electroanal. Chem. (Lausanne Switz.), 2017, 799, 126-133.
Finšgar, M.; Milošev, I. Corrosion study of copper in the presence of benzotriazole and its hydroxy derivative. Mater. Corrosion-Werkstoffe Und Korrosion, 2011, 62(10), 956-966.
Xhanari, K.; Finsgar, M. The first electrochemical and surface analysis of 2-aminobenzimidazole as a corrosion inhibitor for copper in chloride solution. New J. Chem., 2017, 41(15), 7151-7161.
Kologo, S. Voltametry and EQCM study of copper oxidation in acidic solution in presence of chloride ions. Electrochim. Acta, 2007, 52(9), 3105-3113.
Otmačić, H. Protective properties of an inhibitor layer formed on copper in neutral chloride solution. J. Appl. Electrochem., 2004, 34(5), 545-550.
Finšgar, M. Electrochemical analysis of 4-methyl-2-phenyl-imidazole adsorbed on Cu. Int. J. Electrochem. Sci., 2016, 11(8), 6775-6790.
Finšgar, M.; Milošev, I. Corrosion study of copper in the presence of benzotriazole and its hydroxy derivative. Mater. Corros., 2011, 62(10), 956-966.
Lee, H.P.; Nobe, K. Kinetics and mechanisms of Cu electrodissolution in chloride media. J. Electrochem. Soc., 1986, 133(10), 2035-2043.
Crousier, J.; Pardessus, L.; Crousier, J.P. Voltammetry study of copper in chloride solution. Electrochim. Acta, 1988, 33(8), 1039-1042.
Finšgar, M.; Milošev, I. Inhibition of copper corrosion by 1,2,3-benzotriazole: A review. Corros. Sci., 2010, 52(9), 2737-2749.
Finšgar, M. A comparative electrochemical and quantum chemical calculation study of BTAH and BTAOH as copper corrosion inhibitors in near neutral chloride solution. Electrochim. Acta, 2008, 53(28), 8287-8297.
Finšgar, M.; Milošev, I.; Pihlar, B. Inhibition of copper corrosion studied by electrochemical and EQCN techniques. Acta Chim. Slov., 2007, 54(3), 591-597.
Antonijević, M.M.; Milić, S.M.; Petrović, M.B. Films formed on copper surface in chloride media in the presence of azoles. Corros. Sci., 2009, 51(6), 1228-1237.
Antonijević, M.M.; Petrović, M.B. Copper corrosion inhibitors. A review. Int. J. Electrochem. Sci., 2008, 3, 1-28.
Finšgar, M.; Kek Merl, D. 2-Mercaptobenzoxazole as a copper corrosion inhibitor in chloride solution: Electrochemistry, 3D-profilometry, and XPS surface analysis. Corros. Sci., 2014, 80, 82-95.
Finšgar, M.; Kek Merl, D. An electrochemical, long-term immersion, and XPS study of 2-mercaptobenzothiazole as a copper corrosion inhibitor in chloride solution. Corros. Sci., 2014, 83, 164-175.
Finšgar, M. 2-mercaptobenzimidazole as a copper corrosion inhibitor: Part I. Long-term immersion, 3D-profilometry, and electrochemistry. Corros. Sci., 2013, 72, 82-89.
Finšgar, M. 2-Mercaptobenzimidazole as a Copper Corrosion Inhibitor: Part II. Surface Analysis Using X-ray Photoelectron Spectroscopy. Corros. Sci., 2013, 72, 90-98.
Finšgar, M.; Kovač, J.; Milošev, I. Surface analysis of 1-Hydroxybenzotriazole and Benzotriazole adsorbed on Cu by X-Ray photoelectron spectroscopy. J. Electrochem. Soc., 2010, 157(2), C52-C60.
Finšgar, M. EQCM and XPS analysis of 1,2,4-triazole and 3-amino-1,2,4-triazole as copper corrosion inhibitors in chloride solution. Corros. Sci., 2013, 77, 350-359.
Brownson, D.A.C.; Banks, C.E. Interpreting Electrochemistry in The Handbook of Graphene Electrochemistry; Springer London: London, 2014, pp. 23-77.
Srinivasan, S.; Gileadi, E. The potential-sweep method: A theoretical analysis. Electrochim. Acta, 1966, 11, 321-335.
Calandra, A.J. Potentiodynamic current/potential relations for film formation under OHMIC resistance control. Electrochim. Acta, 1974, 19(12), 901-905.
Muller, W.J. On the passivity of metals. Trans. Faraday Soc., 1931, 27(0), 737-751.
Finšgar, M. The corrosion inhibition of certain azoles on steel in chloride media: Electrochemistry and surface analysis. Corros. Sci., 2016, 111(Suppl. C), 370-381.
Tromans, D.; Silva, J.C. Anodic behavior of copper in Chloride/Tolytriazole and Chloride/Benzotriazole solutions. Corrosion, 1997, 53(1), 16-25.
Berzins, T.; Delahay, P. Oscillographic Polarographic Waves for the Reversible Deposition of Metals on Solid Electrodes. J. Am. Chem. Soc., 1953, 75(3), 555-559.
Uchida, Y.; Kätelhön, E.; Compton, R.G. Cyclic voltammetry with non-triangular waveforms: Electrochemically reversible systems. J. Electroanal. Chem., 2017, 801(Suppl. C), 381-387.
Almeida, C.M.V.B.; Giannetti, B.F. Protective film growth on tin in perchlorate and citric acid electrolytes. Mater. Chem. Phys., 2001, 69(1), 261-266.
de Mele, M.F.L. Kinetics and mechanism of silver chloride electroformation during the localized electrodissolution of silver in solutions containing sodium chloride. J. Electrochem. Soc., 1986, 133(4), 746-752.
Torresi, R.M.; De Pauli, C.P. Voltametric behaviour of anodic titanium oxide films close to the hydrogen evolution reaction. Thin Solid Films, 1988, 162, 353-364.
Hassan, H.H.; Fahmy, K. Pitting corrosion of tin by acetate anion in acidic media. Int. J. Electrochem. Sci., 2008, 3, 29-43.
Finšgar, M. X-ray excited Auger Cu L3L4,5M4,5 spectra measured at low take-off angles as a fingerprint for a Cu‐organics connection. J. Electron Spectrosc. Relat. Phenom., 2018, 222(Suppl. C), 10-14.

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