Nucleación y crecimiento de Ag sobre carbón vítreo y obtención de nanopartículas bimetálicas de Ag-Cd

RUBÉN E. AMBRUSI; SILVANA G. GARCÍA

Pto. Iguazú

Simposio; 13er Congreso Internacional en Ciencia y Tecnología de Metalurgia y Materiales (SAM/CONAMET); 2013

The aim of this work is the analysis of the early stages in the process of electrodeposition of Ag on glassy carbon (GC) and the subsequent formation of Cd-Ag bimetallic nanoparticles obtained by underpotential deposition (UPD). To do this we used AFM microscopy and electrochemical techniques. It was established that the process of electrodeposition of Ag on CV corresponds to a pattern of behavior tending to an instantaneous nucleation and 3D diffusion-controlled growth, corroborating this behavior by AFM. Were also determined, the kinetic parameters of the process. Then the substrate modified of GC with Ag nanoparticles, was immersed in a solution containing Cd2 + ions in order to underpotential deposited the Cd selectively on the existing Ag crystallites. The Cd-Ag bimetallic particles obtained were characterized by AFM. The analysis of the desorption spectra of the deposits of Cd, allowed the evaluation of surface alloying between the metals involved