Técnicas electroquímicas para discriminar las diferentes etapas del proceso de electrocristalización de plata en disoluciones acuosas de etilamina y amoníaco
The physical or structural properties of metals in both macroscopic (electroplating) and microscopic (nanoparticle formation) electrodeposition, require adequate control of the electrochemical phase formation processes. During an electrochemical phase formation, several steps are involved in the dep...
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión publicada |
| Fecha de publicación: | 1999 |
| País: | México |
| Institución: | Universidad Autónoma Metropolitana |
| Repositorio: | Repositorio Institucional de la UAM Iztapalapa |
| Idioma: | español |
| OAI Identifier: | oai:bindani.izt.uam.mx:9g54xh99r |
| Acceso en línea: | https://doi.org/10.24275/uami.9g54xh99r |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/LEM/Electrocrystallization info:eu-repo/classification/LEM/Electrocristalización info:eu-repo/classification/LEM/Metallic films info:eu-repo/classification/LEM/Películas metálicas info:eu-repo/classification/cti/2 |
| Sumario: | The physical or structural properties of metals in both macroscopic (electroplating) and microscopic (nanoparticle formation) electrodeposition, require adequate control of the electrochemical phase formation processes. During an electrochemical phase formation, several steps are involved in the deposition process; these are: diffusion of the electroactive species, partial or complete loss of the solvation sheath, adsorption, charge transfer, nucleation and growth. Each one of these steps is influenced by the electrolyte composition, current density, temperature and electrode potential. Such influences would also induce changes in the kinetic parameters that describe this process. It is important to determine quantitatively the influence of the experimental parameters on the different steps in the electrocrystallization process as well as their relationship with the final state and the properties of a metal deposit. In this work we present an electrochemical study of silver electrocrystallization from two electrolytic baths, ethylamine and ammonia in an aqueous medium respectively. These two baths are proposed as an environmentally friendly alternative to the highly toxic cyanide baths. Considering the specific experimental conditions, such as the different coordination spheres of the metal ions (ethylamine and ammonia), the changes in the concentration of the electroactive species, the substrate preparation and the overpotential deposition, it was possible to define and characterise quantitatively each step in the electrocrystallization processes, using different electrochemical techniques. |
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