Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water

Andrew Christy, Adrian Lowe, Vincent Otieno-Alego, M Stoll, Richard Webster

    Research output: Contribution to journalArticle

    70 Citations (Scopus)

    Abstract

    Artificial copper pits were prepared by electrochemically oxidising 60–80 μm diameter copper wires embedded in an epoxy resin over periods of 12–14 h. The electrolyte matrix consisted of various combinations of approximately 40 ppm unbuffered solutions (pH = 6–8) of sodium salts of Cl−, HCO3− and SO42− that are similar in concentration to what are found in potable water supplies in many metropolitan areas throughout the world. It was found that in the concentrations used for the study, HCO3− and to a lesser degree Cl− had a positive affect on preventing pit growth under potentiostatic control, with both anions causing passivation of the copper metal. On the other hand, SO42− was found to be very aggressive to copper dissolution and led to the formation of relatively deep pits (about 0.5 mm). Raman microspectroscopic analyses were performed on the freshly prepared undried caps that formed at the top of the pits and allowed the identification of several corrosion products by a comparison with standard copper mineral samples. The most complicated cap structure was observed in the presence of all three anions with distinct regions of the pit corresponding to cuprite (Cu2O), eriochalcite (CuCl2 · 2H2O), atacamite and/or botallackite [Cu2Cl(OH)3] and brochantite [Cu4(SO4)(OH)6]
    Original languageEnglish
    Pages (from-to)225-233
    Number of pages9
    JournalJournal of Applied Electrochemistry
    Volume34
    Issue number2
    Publication statusPublished - 2004

    Fingerprint

    Potable water
    Drinking Water
    Copper
    Anions
    Negative ions
    Epoxy Resins
    Water supply
    Passivation
    Epoxy resins
    Electrolytes
    Minerals
    Dissolution
    Salts
    Metals
    Sodium
    Wire
    Corrosion

    Cite this

    Christy, Andrew ; Lowe, Adrian ; Otieno-Alego, Vincent ; Stoll, M ; Webster, Richard. / Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water. In: Journal of Applied Electrochemistry. 2004 ; Vol. 34, No. 2. pp. 225-233.
    @article{2a920ac4e20a4d25945ee16d29e07917,
    title = "Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water",
    abstract = "Artificial copper pits were prepared by electrochemically oxidising 60–80 μm diameter copper wires embedded in an epoxy resin over periods of 12–14 h. The electrolyte matrix consisted of various combinations of approximately 40 ppm unbuffered solutions (pH = 6–8) of sodium salts of Cl−, HCO3− and SO42− that are similar in concentration to what are found in potable water supplies in many metropolitan areas throughout the world. It was found that in the concentrations used for the study, HCO3− and to a lesser degree Cl− had a positive affect on preventing pit growth under potentiostatic control, with both anions causing passivation of the copper metal. On the other hand, SO42− was found to be very aggressive to copper dissolution and led to the formation of relatively deep pits (about 0.5 mm). Raman microspectroscopic analyses were performed on the freshly prepared undried caps that formed at the top of the pits and allowed the identification of several corrosion products by a comparison with standard copper mineral samples. The most complicated cap structure was observed in the presence of all three anions with distinct regions of the pit corresponding to cuprite (Cu2O), eriochalcite (CuCl2 · 2H2O), atacamite and/or botallackite [Cu2Cl(OH)3] and brochantite [Cu4(SO4)(OH)6]",
    author = "Andrew Christy and Adrian Lowe and Vincent Otieno-Alego and M Stoll and Richard Webster",
    year = "2004",
    language = "English",
    volume = "34",
    pages = "225--233",
    journal = "Journal of Applied Electrochemistry",
    issn = "0021-891X",
    publisher = "Springer",
    number = "2",

    }

    Christy, A, Lowe, A, Otieno-Alego, V, Stoll, M & Webster, R 2004, 'Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water', Journal of Applied Electrochemistry, vol. 34, no. 2, pp. 225-233.

    Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water. / Christy, Andrew; Lowe, Adrian; Otieno-Alego, Vincent; Stoll, M; Webster, Richard.

    In: Journal of Applied Electrochemistry, Vol. 34, No. 2, 2004, p. 225-233.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Voltammetric and Raman microspectroscopic studies on artificial copper pits grown in simulated potable water

    AU - Christy, Andrew

    AU - Lowe, Adrian

    AU - Otieno-Alego, Vincent

    AU - Stoll, M

    AU - Webster, Richard

    PY - 2004

    Y1 - 2004

    N2 - Artificial copper pits were prepared by electrochemically oxidising 60–80 μm diameter copper wires embedded in an epoxy resin over periods of 12–14 h. The electrolyte matrix consisted of various combinations of approximately 40 ppm unbuffered solutions (pH = 6–8) of sodium salts of Cl−, HCO3− and SO42− that are similar in concentration to what are found in potable water supplies in many metropolitan areas throughout the world. It was found that in the concentrations used for the study, HCO3− and to a lesser degree Cl− had a positive affect on preventing pit growth under potentiostatic control, with both anions causing passivation of the copper metal. On the other hand, SO42− was found to be very aggressive to copper dissolution and led to the formation of relatively deep pits (about 0.5 mm). Raman microspectroscopic analyses were performed on the freshly prepared undried caps that formed at the top of the pits and allowed the identification of several corrosion products by a comparison with standard copper mineral samples. The most complicated cap structure was observed in the presence of all three anions with distinct regions of the pit corresponding to cuprite (Cu2O), eriochalcite (CuCl2 · 2H2O), atacamite and/or botallackite [Cu2Cl(OH)3] and brochantite [Cu4(SO4)(OH)6]

    AB - Artificial copper pits were prepared by electrochemically oxidising 60–80 μm diameter copper wires embedded in an epoxy resin over periods of 12–14 h. The electrolyte matrix consisted of various combinations of approximately 40 ppm unbuffered solutions (pH = 6–8) of sodium salts of Cl−, HCO3− and SO42− that are similar in concentration to what are found in potable water supplies in many metropolitan areas throughout the world. It was found that in the concentrations used for the study, HCO3− and to a lesser degree Cl− had a positive affect on preventing pit growth under potentiostatic control, with both anions causing passivation of the copper metal. On the other hand, SO42− was found to be very aggressive to copper dissolution and led to the formation of relatively deep pits (about 0.5 mm). Raman microspectroscopic analyses were performed on the freshly prepared undried caps that formed at the top of the pits and allowed the identification of several corrosion products by a comparison with standard copper mineral samples. The most complicated cap structure was observed in the presence of all three anions with distinct regions of the pit corresponding to cuprite (Cu2O), eriochalcite (CuCl2 · 2H2O), atacamite and/or botallackite [Cu2Cl(OH)3] and brochantite [Cu4(SO4)(OH)6]

    M3 - Article

    VL - 34

    SP - 225

    EP - 233

    JO - Journal of Applied Electrochemistry

    JF - Journal of Applied Electrochemistry

    SN - 0021-891X

    IS - 2

    ER -