The oxidation of artificial cuprous sulphide electrodes (Cu/S ratio = 1.93) was studied in acidified copper sulphate solutions in the temperature range 20 to 35° C. Rest potential measurements gave V° = 0.490 volts for the electrode or half cell potential. This is within the limits of accuracy of V° for:
Cu₂S —CuS + Cu⁺⁺ + 2e V° = 0.535 + 0.13 volts
The discrepancy was thought to be related to the large Cu deficien in the sulphide. In solutions with pH>4, the rest potential measurements were consistent with the following reaction:
Cu₂S + 2H₂0 —CuS + Cu(OH)₂ + 2H⁺ + 2e
Polarization measurements at low overpotential gave values for the following kinetic parameters:
β, the symmetry factor = 1/2
λ, the number of electrons involved in each act of the
rate determining step = 2
i₀, the exchange current ≈ 2 x 10-⁵ A/cm²
ΔH₀*, the standard heat of activation = 26.5 kcal/mole
CuS was tentatively identified as one of the reaction products. A reaction mechanism was discussed. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/37540 |
| Date | January 1965 |
| Creators | Fraser, Michael J. |
| Publisher | University of British Columbia |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
Page generated in 0.0017 seconds