Growth of columnar gold electrodes by electroreducing hydrous gold oxide layers : Kinetics and mechanistic interpretation

Rough columnar structured gold electrodeposits were prepared in aqueous 0.5 M M H2SO4 by electroreducing a hydrous gold oxide layer built up on a gold substrate by means of a fast periodic potential routine. The analysis of potentiodynamic and potentiostatic hydrous oxide layer electroreduction data...

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Autores principales: Vela, María Elena, Marchiano, Susana Lucy, Salvarezza, Roberto Carlos, Arvia, Alejandro Jorge
Formato: Articulo
Lenguaje:Inglés
Publicado: 1995
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Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/121129
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Sumario:Rough columnar structured gold electrodeposits were prepared in aqueous 0.5 M M H2SO4 by electroreducing a hydrous gold oxide layer built up on a gold substrate by means of a fast periodic potential routine. The analysis of potentiodynamic and potentiostatic hydrous oxide layer electroreduction data indicated the initial nucleation of gold clusters at the metals|oxide interface. The growth of gold nuclei proceeded under a constant capture area condition for depositing gold ions contained in the hydrous oxide layer. Columnar gold electrodeposition was assisted by the gel-like characteristics of the hydrous gold oxide layer. Gold columnar growth ended as soon as the column tips reached the oxide s| solution interfacc. The proposed kinetic model accounts for the high surface area development and surface fractal properties of this type of metal electrode.