INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
“Underpotential deposition on metal nanoparticles: Theoretical considerations and computer simulations”
Autor/es:
LEIVA, EZEQUIEL PEDRO MARCOS
Lugar:
Boston
Reunión:
Congreso; 220 ECS Meeting in Boston & Electrochemical Energy Summit; 2011
Institución organizadora:
Electrochemical Society
Resumen:
The singular properties of metallic nanoparticles(NP) have awaked great interest in both the scientific and technological communities, and the size-dependence of their thermodynamic properties has been a hot topic of research in recent years. Currently, there are several methods to control the size of metallic NP. In those cases where NP growth is controlled by a redox system, the chemical identity of the redox species and/or the concentration ratio between the surfactant and the precursor agent [1] constitute the main variables. While extensive experimental effort has been devoted to understand this phenomenon, there are very few examples on theoretical modeling available to unveil the role played by each of these variables on the final size of the NP. On the general context, our talk will discuss on the feasibility of the extension of underpotential deposition and overpotential deposition concepts to metallic NP. We present here a statistical mechanical model [2-4] aimed at establishing the role played by each of the following variables: nature and activity of the surfactant and reactants, the size, shape and metallic nature of the NP, and the effect of the super and undersaturation conditions. A brief discussion on the model will be made illustrating its application with computer simulation using realistic interatomic potentials. The thermodynamic stability of different structures like Au/Ag, Pd/Au, and Pt/Au will be presented, and possible experiments to test the model will be proposed based on simulations of their optical properties.