A molecular-beam study of methane dissociative adsorption on oxygen-precovered Pt{110}(1×2)

Molecular-beam techniques have been used to determine the effect of oxygen adatoms on the dissociative adsorption of CH4 at a surface temperature of 400 K. The initial sticking probability, s0, is always smaller than that for the clean surface in the energy range studied, 90 meV≤Et≤500 meV and at oxygen precoverages up to one monlayer. As the internal energy of the incident CH4 is increased, s0 for the clean and oxygen-precovered surfaces converges; oxygen blocks fewer surface sites to methane dissociative adsorption. Carbon adatoms, formed from the dissociative adsorption of CH4, react readily with Oa to form CO.