CO Oxidation over a Pt(100) Surface in a Ternary Gas Mixture of CO, NO, and Oxygen

Abstract

Abstract Catalytic CO oxidation in a ternary gas mixture of CO, NO and O2 has been studied in the 10–5–10–4 mbar range using a Pt(100) sample as catalyst. Measurements of the reactive sticking coefficients of CO and NO are used to decompose the overall CO oxidation rate into the contributions from oxidation by NO and from oxidation by O2. The experiments are complemented by simulations with a realistic 7-variable model. The surface phase transition hex ↔ 1×1 and the inhibition of NO dissociation and O2 adsorption at high adsorbate coverages lead to significant hysteresis effects.