Surface Reaction Dynamics via Temperature Modulation: Applications to the Oxidation of Carbon Monoxide on the Pt(110)-(1×2) Surface

The novel application of a surface-temperature-modulation technique to the important class of bimolecular surface reactions is shown to lead to detailed dynamical information in a direct fashion. Knowledge of the adlayer composition or structure is not required for an evaluation of the activation energy. The activation barrier for the reaction CO(a) +O(a) → C${\mathrm{O}}_2$(g) on the Pt(110) surface is found to decrease precipitously from a value of 22 kcal-${\mathrm{mol}}^{-1\mathrm{}}$ at low coverages to a value of approximately 8 kcal-${\mathrm{mol}}^{-1\mathrm{}}$ in the presence of high coverages of oxygen adatoms.