Theoretical Study of Catalytic CO Oxidation on (111) Metal Surfaces: Calculating Rate Constants That Account for Tunnel Effect
journal contributionposted on 05.07.2007, 00:00 by Ernst D. German, Moshe Sheintuch
An approximate analytical approach is suggested to calculate kinetic parameters for the catalytic oxidation of carbon monoxide on the (111) surfaces of transition metals of platinum, palladium, iridium, rhodium, and nickel. The origin of the activation barriers is discussed in terms of the decomposition analysis. Tunnel effect along the reaction coordinate is considered. An interpretation of possible non-Arrhenius behavior of rate constant of the CO oxidation reactions is suggested in terms of the tunneling. Temperature dependencies of the activation energies are calculated. Isotope effect under substitution of C(12) by C(14) is predicted. Experimental data are interpreted using the developed approach. Relationships between the activation energies and rate constants calculated accounting for quantum effects and the corresponding surface reaction energies are discussed.