Numerical simulation of electrochemical adsorption process by kinetic Monte Carlo methods
Electrocatalytic reactions are of great interest for fuel cell technology. Oxidation reactions, such as the transformation of CO to CO2 and the dissociative chemisorption of small alcohols are influenced by the presence of anions. Thus, the incorporation of anion adsorption into kinetic models for these small molecule oxidation reactions is desired to develop mechanisms of experimentally practical systems. This dissertation focuses on models for anion adsorption that can be applied in more realistic kinetic descriptions of small molecule oxidation reactions. In this work, anion adsorption is modeled through the use of kinetic Monte Carlo (kMC) methods. An overview of the formulation, implementation, application and challenges is provided. Then, the adsorption of anions to form several overlayer structures, such as p(2x2) and (r3×r3)R30 on (100) and (111) electrode surfaces during linear scan voltammograms are modeled. Simple lateral interaction models were tested initially and formed a foundation for approaching more complicated adlayer structures that are representative of practical systems. The overall goal was to develop reaction schemes for anion adsorption on (111) and (100) planes that can be incorporated into models for small molecule oxidation reactions to improve the predictive capabilities of the simulations.