Periodic current oscillations at the gold/acid aqueous interfaces induced by HCl additions
The periodic oscillating current recorded under a constant potential step for Au/acid solution interfaces containing different concentrations of Cl− ion is studied in the 25–50°C range. Two main electrochemical reactions coupled to two diffusion processes are responsible for the periodic effect. The...
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| Autores principales: | , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
1979
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/122403 https://www.sciencedirect.com/science/article/abs/pii/0013468679870449 |
| Aporte de: |
| Sumario: | The periodic oscillating current recorded under a constant potential step for Au/acid solution interfaces containing different concentrations of Cl− ion is studied in the 25–50°C range. Two main electrochemical reactions coupled to two diffusion processes are responsible for the periodic effect. The electrochemical reactions occurring successively are the electrodissolution of gold as the AuCl−2 complex, a reaction which is diffusion controlled and then the oxide layer formation when the solution is depleted of Cl− ion. Subsequently, as the anodic current decreases due to the electrode passivation, the HCl diffuses backwards and dissolves the oxide film. The active part of the periodic cycle is interpreted in terms of a diffusional process involving at its initiation the simultaneous uncoverage of the electrode surface. |
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