Catalytic reactions of dioxygen with ethane and methane on platinum clusters: Mechanistic connections, site requirements, and consequences of chemisorbed oxygen

► C2H6O2 and CH4O2 form CO2 and H2O via similar elementary steps on Pt clusters. ► Elementary steps and rate equations depend on oxygen (O*) coverages. ► O* coverages are set by kinetic coupling between CH and OO activation steps. ► Rates reflect CH strength in alkanes and alkylO* interactions at transition states. ► Strongly bound O* at low-coordination surfaces are less reactive in CH activation.