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Abstract: The meaning of underpotential shift is discussed for free nanoparticles, where a redox couple is used to set potential control on them. Atomistic Monte Carlo simulations are performed to study their decoration in the submonolayer regime. The resulting configurations are used to simulate their plasmon spectra by means of a state-of-the art quantum mechanical atomistic model. [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]

The voltammetric behavior of Li+ intercalation/deintercalation in/from LiMn2O4 thin films and single particles is simulated, supporting very recent experimental results. Experiments and calculations both show that particle size and geometry are crucial for the electrochemical response. A remarkable outcome of this research is that higher potential sweep rates, of the order of several millivolts per second, may be used to characterize nanoparticles by voltammetry sweeps, as compared with macroscopic systems. This is in line with previous conclusions drawn for related single particle systems using kinetic Monte Carlo simulations. The impact of electrode kinetics and finite space diffusion on the reversibility of the process and the finiteness of the diffusion in ion Li / LiMn2O4 (de)intercalation is also discussed in terms of preexisting modeling. [ABSTRACT FROM AUTHOR]

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]