On the extension of the concept of UPD and OPD to the case of metal nanoparticles

O.A. OVIEDO, M. M. MARISCAL, E.P.M. LEIVA

NICE

Congreso; 61 annual meeting of the International Society of Electrochemistry; 2010

International Society of Electrochemistry

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 much experimental effort has been devoted to understand this phenomenon, there are very few examples on the theoretical model available to unveil the role played by each of these variables on the final size of the NP. On the general context, we talk about of the feasibility of the extension of UPD and OPD concept 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 under potential deposition. A brief discussion on the model is 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 presents.