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Abstract: The electrochemical decoration of Au and Pd nanoparticles by Pd and Au atoms respectively is discussed in a statistical mechanical framework. It is found that depending on precursor nanoparticle size and shape, controlled decoration may be achieved in undersaturation or oversaturation conditions. Multilayer deposition is also considered, with the finding that this phenomenon is also size dependent. [Copyright &y& Elsevier]

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]

To delve deeper into the kinetics involved in the staging phenomena of lithium insertion into graphite, it is necessary to develop theoretical models that emulate the physical phenomenon involved. In the present work kinetic Monte Carlo simulations are used to carry out a thorough analysis of the Li-ion graphite system, with the twofold aim of providing atomistic support for interpretations based on several experimental electrochemical techniques commonly used in the laboratory and of making theoretical predictions for future experimental work. Cyclic voltammograms and chronoamperometric transients are obtained, and diffusion coefficients and exchange current densities are calculated at different Li loadings of graphite. These results are compared with selected experimental data from the literature. In this way, there emerge details that cannot be observed in ordinary experiments due to methodological/instrumental limitations. For example, it is found that chronoamperometric responses are different for intercalation and deintercalation, the latter being a faster process. The reason why these phenomena are different is revealed, supporting and widening experimental assumptions. The present results also suggest that the intrinsic hysteresis observed in experimental work (and in simulations) is due to kinetic factors. • Kinetic Monte Carlo simulations emulate electrochemical techniques allowing a deep atomistic study. • Cyclic voltammetry and chronoamperometric simulations profiles provide understanding on experimental results. • Diffusion coefficients and exchange current density predict the behavior of Li-ion in different intercalation levels. • Deintercalation is faster than intercalation, due to the Li-ion clog next to the interphase in the lithiation. • The hysteresis phenomenon is apparently related to a kinetic origin. [ABSTRACT FROM AUTHOR]