Monte Carlo simulations of FTIR studies during CO oxidation on a Pt/SiO2 catalyst

A Monte Carlo (MC) simulation of the reaction of CO with an oxygen covered Pt surface and oxygen with a CO covered Pt surface is presented in this paper. The effect of the adsorption, desorption, reaction, and surface migration rates on the formation of CO clusters is analyzed in terms of the CO frequency shift in the IR spectrum. The MC simulation calculates the CO frequency shifts according to a dipole-dipole interaction model. The IR frequency shifts predicted by the simulation depend on the value of the various kinetic processes considered. The simulation indicates that the CO migration on the surface is important at low pressure but is inhibited at high pressure. The IR frequency shifts predicted by the simulation agree qualitatively with experimental values obtained during CO oxidation on a Pt catalyst.