Open-circuit electrode potential deaeration

There is evidence that the open circuit potential (OCP) of solid alloy electrodes with large AE in deaerated solutions may also be determined by the less noble component, A. However, since there is no equilibration between the surface and the bulk, such OCP reflect the surface activity of the less noble component rather than that of the bulk (4). A more detailed discussion of the thermodynamics of alloy electrodes with due consideration of the Gibbs energy of mixing of the alloy phase has been given by Heusler [5). 

On investigation of electrochemically deposited Ag coatings, it was established [23] that their open-circuit potentials (f g) possess all properties that are characteristic of equilibrium potentials. In contrast with Cu electrodes in cyanide system (see Section 2.4.1), no change in the Ag electrode mass was observed upon its daily exposure to the deaerated Ag(I)-cyanide solution. After the potential step perturbation, the equilibration proceeds rather rapidly and g acquires its initial... 

According to [12], the open-circuit potentials of Au electrodes ( u) immersed into oxygen-containing Au(I) cyanide solutions are corrosion potentials, because products of Oj reduction react with the Au surface forming surface oxides. These compounds are gradually eliminated during deaeration with nitrogen, but this process takes several hours. 

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