EQUILIBRIUM AND NONEQUILIBRIUM APPLICATIONS OF LATTICE-GAS MODELS IN ELECTROCHEMISTRY

We discuss applications of statistical-mechanical lattice-gas models t o study static and dynamic aspects of electrochemical adsorption. The strategy developed to describe specific systems includes microscopic m odel formulation, calculation of zero-temperature phase diagrams, nume rical simulation of thermodynamic and structural quantities at non-zer o temperatures, and estimation of effective lateral interactions. We b riefly review earlier work, including studies by Monte Carlo simulatio n of the adsorption of urea on Pt(100). As an illustrative example, we discuss in some detail recent applications to the underpotential depo sition of Cu with sulfate on Au(111). Experimental and numerical resul ts 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. (C) 1998 Elsevier Science B.V.