Mechanism of anodic dissolution of copper in aqueous acidified solutions of different anions

Awad, S. A.; Kamel, Kh.M.; El-Hadi, Z. A.; Bayumi, H.A.

doi:10.1016/0022-0728(86)80008-0

Cited by 25 publications

(14 citation statements)

References 9 publications

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“…If the Tafel coefficients are calculated for both regions, anodic (b a ) and cathodic (b c ) , the values are 60 and 120 mV decade -1 , respectively, for all NaCl concentrations and pHs, showing that these two features do not affect the Tafel anodic coefficient. This b a value is similar to the one obtained for some authors 11,12 for pure Cu. Awad et al ) in terms of a The same b a value has been obtained for Cu-Al alloys 13,14 with Al compositions in the range 8 to 13 wt.%.…”

Section: Cyclic Voltammetrysupporting

confidence: 76%

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

Serra¹,

Benedetti²,

Noce³

2010

J. Braz. Chem. Soc.

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O comportamento eletroquímico da liga Cu-9%Al-5%Ni-2%Mn em diferentes concentrações de NaCl e valores de pH foi estudado por potencial em circuito aberto (E CA ), voltametria cíclica e curvas de polarização. As curvas E CA mostraram uma considerável influência da concentração de NaCl e do pH da solução nos valores de potencial de estado estacionário. Foi observado pelos perfis I/E que a variação da velocidade de varredura indicou a formação de um filme poroso de baixa condutividade o qual foi o responsável pelo aumento linear de corrente, devido à resistência da solução contida nos poros do filme. Com o intuito de investigar os produtos formados durante a varredura de potencial, o potencial foi mantido em diferentes valores de potencial aplicado dos voltamogramas cíclicos e analisado por MO, MEV e EDX. Em geral, foi observada a presença de precipitados de CuCl em potenciais aplicados iguais a 0,20; 0,85 e 0,00 V (vs. Ag/AgCl/KCl (3 mol L -1 ) ) e somente Cu em -0,70; -1,00 e -1,35 V. Nestes últimos, uma camada de Cu foi observada na superfície da liga devido à redução de cloreto cuproso. Este filme bloqueou o aparecimento dos picos de EDX relacionados aos outros metais presentes na liga. As curvas de polarização para a liga Cu-9%Al-5%Ni-2%Mn mostraram que E CA variou conforme o pH da solução e a concentração de NaCl. Conforme a concentração de NaCl aumentou, E CA tornou-se mais negativo para os três valores de pH estudados. Os coeficientes de Tafel foram calculados das curvas de polarização e os valores foram de 60 e 120 mV década -1 , para a região anódica e catódica, respectivamente.The electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in different NaCl concentrantions and pHs was studied by means of open-circuit potential (E OC ), cyclic voltammetry and polarization curves. The E OC curves showed a considerable influence of NaCl concentration and solution pH in the steady-state potential values. It was observed by the I/E profiles that the scan rate variation indicated the formation of a porous film of low conductivity which was the responsible by the linear increase of current due to the solution resistance contained in the film pores. In order to investigate the products formed during the potential scan, the potential was held at different values of applied potential of the cyclic voltammogram and analyzed by OM, SEM and EDS. In general, it was noticed the presence of CuCl precipitates in applied potentials equals to 0.20, 0.85 and 0.00 V (vs. Ag/AgCl/KCl (3 mol L -1 ) ) and only Cu in -0.70, -1.00 and -1.35 V. In the latter cases, a Cu layer was observed on the alloy surface due to the cuprous chloride reduction. This film blocked the EDS peaks appearance related to the other metals present in the alloy. The polarization curves for Cu-9%Al-5%Ni-2%Mn showed that E OC varied according to the solution pH and NaCl concentration. As the NaCl concentrantion increased the E OC became more negative for the three pHs studied. The Tafel coefficients were calculated from the polarization curves and the values were ...

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Section: Cyclic Voltammetrysupporting

confidence: 76%

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

Serra¹,

Benedetti²,

Noce³

2010

J. Braz. Chem. Soc.

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“…Considerons le cas ou le cuivre se dissout sous forme de cu2+ et ou 1e transfert de masse fait intervenir la diffusion du Cu2+ form6 ti 1 Un mCcanisme conduisant a la formation de Cu2+ peut &tre envisagC (12 (27), ce qui conduit dans ce cas a une valeur pour la pente de Tafel de 30 mV.…”

Section: Resultats Et Discussionunclassified

La dissolution anodique du cuivre en présence d'ions F⁻ dans des solutions aqueuses acides

Potvin¹,

Drogowska²,

Ménard³

et al. 1987

Can. J. Chem.

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The influence of F− ions on the anodic dissolution of copper in aqueous acidic solutions (pH 1.6–6), mainly at pH 5 with 0.1 M KF, has been studied. The nature of the changes that occur on the electrode during the oxidation has been examined by cyclic voltamperometry as well as by different techniques of surface analysis (SEM, XPS, AES). To determine the mechanism of the electrochemical oxidation of copper at pH 5, studies with rotating disk electrodes have been carried out under conditions giving rise to a general dissolution of copper. At pH 1.6–6, the copper electrode dissolves uniformly, i.e., without preferential zones on the surface, when it is submitted to a potentiodynamic polarization (10 mV s−1) at potentials above 0 VECS. At slightly acidic pH (pH 5, KF0.1 M), with a sweep of potential up to +0.5 V, the oxidation of copper begins with a generalized corrosion of the electrode and it is followed by the formation of a film of Cu2O that is not passivating; as the oxidation proceeds, the current drops and the electrode becomes passivated. One model for the anodic dissolution is presented for the results obtained at pH 5. When a uniform corrosion develops on the rotating electrode, the copper is oxidized to Cu2+ ions. When ω → 0, the rate of dissolution of the electrode is limited by the diffusion of the Cu2+ ions from the electrode to the solution, whereas when ω → ∞ the process of charge transfer is the limiting factor to the kinetics of the dissolution. [Journal translation]

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“…The bone of contention is the existence form of Cu(I), which may be Cu + , 20 Cu(I) ads 21,22 or cuprous compounds (a fast reaction). 23 It is generally accepted that the corrosion product at high potentials is Cu(II).…”

Section: Discussionmentioning

confidence: 99%

Investigation into the Anodic Dissolution Processes of Copper in Neutral and Acidic Sulfate Solutions with the In-line Digital Holography

Jiao

et al. 2016

Electrochemistry

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The films formed on the surface of copper during its anodic dissolution in the neutral or acidic sulfate solution were studied with the in-line digital holography. The results showed that the mixture films were formed on the surface of copper in the neutral or acidic sulfate solution: the inner oxide film and the outer salt film. Although there are defects in the oxide film caused by the sulfate ions, the oxide film other than the salt film mainly inhibits the anodic dissolution at the high anodic potentials.

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Mechanism of anodic dissolution of copper in aqueous acidified solutions of different anions

Cited by 25 publications

References 9 publications

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

La dissolution anodique du cuivre en présence d'ions F⁻ dans des solutions aqueuses acides

Investigation into the Anodic Dissolution Processes of Copper in Neutral and Acidic Sulfate Solutions with the In-line Digital Holography

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Mechanism of anodic dissolution of copper in aqueous acidified solutions of different anions

Cited by 25 publications

References 9 publications

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

Electrochemical behavior of Cu-9%Al-5%Ni-2%Mn alloy in chloride media

La dissolution anodique du cuivre en présence d'ions F− dans des solutions aqueuses acides

Investigation into the Anodic Dissolution Processes of Copper in Neutral and Acidic Sulfate Solutions with the In-line Digital Holography

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La dissolution anodique du cuivre en présence d'ions F⁻ dans des solutions aqueuses acides