A comparative electrochemical and ellipsometric study of the iron electrodes in different alkaline electrolytes
The electrochemical and ellipsometric responses of iron electrodes in 0.04 M NaOH and in saturated Ca(OH)<sub>2</sub> are investigated at 25°C, in the potential range where the passivating layer in the absence of oxygen under potential controlled and non-equilibrium conditions is formed....
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| Autores principales: | , , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
1986
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/82352 |
| Aporte de: |
| Sumario: | The electrochemical and ellipsometric responses of iron electrodes in 0.04 M NaOH and in saturated Ca(OH)<sub>2</sub> are investigated at 25°C, in the potential range where the passivating layer in the absence of oxygen under potential controlled and non-equilibrium conditions is formed. From the correlation of results a composite structure of the passivating layer is envisaged involving an inner layer which is difficult to electroreduce, probably related to Fe<sub>3</sub>O<sub>4</sub>, and an outer gelatinous iron hydroxide layer where a relatively fast, Fe(II)/Fe(III) redox process can be voltammetrically followed.
The inhibitive properties of saturated Ca(OH)<sub>2</sub> as compared to 0.04 M NaOH are explained through the absorption of Ca<sup>2+</sup> ions at the outer plane of the inner part of the passivating film and the corresponding transport of water into the gelatinous part of the passivating film. |
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