Quantifying oxygen induced surface enrichment of a dilute PdAu alloy catalyst

Dilute PdAu alloys are promising catalysts for selective oxidation and hydrogenation reactions. However, the surface composition and active site density of the minority metal, Pd, is unknown. In this study, we quantitatively determine a three-fold increase in the Pd site density on the surface of a dilute Pd0.08Au0.92 alloy catalyst after oxygen activation by titrating the oxidized surface with quantified pulses of CO.