DFT study of CO oxidation over Au/TiO2(1 1 0): The extent of the reactive perimeter zone

O2 adsorption and CO oxidation on a Au/rutile TiO2(1 1 0) catalyst have been examined by DFT in order to define the extent of the reactive perimeter zone. O2 is found to adsorb on the fivefold coordinated Ti sites that are away from the perimeter as well as on those next to the perimeter. Both O2 show similar reactivity toward a gaseous CO. CO oxidation still occurs predominantly at the perimeter because O2 adsorption is strongest at the perimeter Ti site and because CO is activated on Au through back donation.