Equilibrium and nonequilibrium applications of lattice-gas models in electrochemistry

TL;DR

This paper explores how lattice-gas models can be used to understand static and dynamic electrochemical adsorption phenomena, including recent simulations of current transients during potential changes.

Contribution

It introduces a comprehensive approach combining microscopic modeling, phase diagram calculation, and Monte Carlo simulations for electrochemical systems.

Findings

Agreement between simulations and experimental data for equilibrium coverages.

Successful modeling of voltammetric currents at slow potential sweep rates.

New dynamic Monte Carlo results for current transients after potential jumps.

Abstract

We discuss applications of statistical-mechanical lattice-gas models to study static and dynamic aspects of electrochemical adsorption. The strategy developed to describe specific systems includes microscopic model formulation, calculation of zero-temperature phase diagrams, numerical simulation of thermodynamic and structural quantities at nonzero temperatures, and estimation of effective, lateral interactions. We briefly review earlier work, including studies by Monte Carlo simulation of the adsorption of urea on Pt(100). As an illustrative example, we discuss in some detail recent applications to the underpotential deposition of Cu with sulfate on Au(111). Experimental and numerical results are included for equilibrium coverages and voltammetric currents at slow potential sweep rates, and new results from dynamic Monte Carlo simulations are presented. In particular, we present simulated results for current transients far from equilibrium, following sudden changes in the electrode potential.