A molecular beam scattering investigation of the oxidation of CO on Rh(111). I. Kinetics and mechanism

Publisher Website
Google Scholar
Abstract
The catalytic oxidation of carbon monoxide on a Rh(111) surface has been investigated using modulated molecular beam techniques. Reaction proceeds via a Langmuir–Hinshelwood mechanism. Under experimental conditions which provide a high coverage of oxygen adatoms and near zero coverage of adsorbed CO, an activation energy of 24.5±0.4 kcal/mol and a preexponential factor of 2±1×10−3 cm2 s−1 were obtained. The angular distribution of the product CO2 is sharply peaked toward the surface normal, and cannot be described by a simple cosnθ expression. Present results are discussed in relation to previous work on platinum and palladium surfaces.