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Abstract: In the present work we discuss the statistical mechanical framework for predicting the decoration of metallic nanoparticles using electrochemical methods, in thermodynamic equilibrium. It is found that depending on the interactions between the two metals, controlled decoration may be achieved for core–shell nanoparticles in undersaturation and oversaturation conditions. The concept of underpotential deposition is discussed for the case of nanoparticles, with the finding that this phenomenon may be size dependent. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical deposition of a metal on a foreign substrate may occur before or after the Nernst reversible potential, depending on the chemical nature of the substrate and adsorbate in question. Statistical mechanical treatment and a proper description of interactions between the particles of the system are necessary for an adequate theoretical representation of the electrochemical systems. In the present work, changes in relevant thermodynamic properties due to adsorption of a metal on a foreign single crystal (h k l) metallic surface are studied for a number of systems of electrochemical interest by means of quasi-harmonic (QH) lattice dynamics calculations with embedded atom method potentials at 300K. The metal couples considered involve silver, gold, platinum, palladium and copper. Underpotential and overpotential deposition trends observed for this set of transition metal systems are analyzed taking into account the changes in the internal energies and the entropic contributions due to deposition processes. The possibility of obtaining entropic information from measurements at different temperatures is also discussed. [Copyright &y& Elsevier]

Abstract: In order to contribute to the understanding of metal electrodeposition on real surfaces, we consider in the present work the deposition of Ag, Cu and Pd on a Pt(111) surface with defects. Off lattice Monte-Carlo simulations were performed using embedded atom method Potentials in the canonical ensemble at 300 K. Structural and energetic properties of deposits on surface defects of low dimension (iD=0,1,2) were studied. Among others, we consider vacancies (0D), steps (1D) and holes (2D). The results obtained are in qualitative agreement with experimental data in the literature. [Copyright &y& Elsevier]