The role of a slow phase formation process in the growth of anodic silver oxide layers in alkaline solutions : I. Electroformation of Ag(I) oxide layer
The anodic electroformation of silver (I) oxide layer on polycrystalline silver electrodes in 0.1 M NaOH was studied by using potentiodynamic and potentiostatic techniques. The growth of the silver oxide layer under a linear potential sweep or potential step measurements involves as a first step the...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 1988 |
| País: | Argentina |
| Institución: | Universidad Nacional de La Plata |
| Repositorio: | SEDICI (UNLP) |
| Idioma: | inglés |
| OAI Identifier: | oai:sedici.unlp.edu.ar:10915/83436 |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/83436 |
| Access Level: | acceso abierto |
| Palabra clave: | Ciencias Exactas Química Compuestos de Plata Óxidos Soluciones Metales Alcalinos Electrodos electroformation Plata |
| Sumario: | The anodic electroformation of silver (I) oxide layer on polycrystalline silver electrodes in 0.1 M NaOH was studied by using potentiodynamic and potentiostatic techniques. The growth of the silver oxide layer under a linear potential sweep or potential step measurements involves as a first step the electroformation of Ag<sub>2</sub>O or AgOH monolayer at potentials close to the Ag/Ag<sub>2</sub>O reversible electrode potential. This monolayer grows through a solid diffusion mechanism to form a 3-D primary silver (I) oxide. Subsequently the building up of a secondary silver (I) oxide layer is clearly noticed when the potential exceeds 0.24 V (vs sce). The formation of this layer can be described in terms of an instantaneous nucleation and 3-D growth mechanism under diffusion control. The ageing effects at the primary layer level decreases the nucleation rate so that for the growth of the secondary layer an intermediate situation between instantaneous and progressive nucleation under diffusion control can be observed. The secondary silver (I) oxide layer can be related to the aged silver (I) oxide species previously reported. |
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