Surface Lattice-Embedded Pt Single-Atom Catalyst on Ceria-Zirconia with Superior Catalytic Performance for Propane Oxidation

Ahighly efficient Pt single-atom catalyst was constructedon pre-stabilized Ce0.9Zr0.1O2 supportvia high-temperature calcination for catalytic oxidation of C3H8. Tuning the metal-support interaction and coordinationenvironmentof single-atom catalysts can help achieve satisfactory catalytic performancefor targeted reactions. Herein, via the facile control of calcinationtemperatures for Pt catalysts on pre-stabilized Ce0.9Zr0.1O2 (CZO) support, Pt single atoms (Pt-1) with different strengths of Pt-CeO2 interactionand coordination environment were successfully constructed. With theincrease in calcination temperature from 350 to 750 & DEG;C, a strongerPt-CeO2 interaction and higher Pt-O-Ce coordinationnumber were achieved due to the reaction between PtO x and surface Ce3+ species as well as the migrationof Pt-1 into the surface lattice of CZO. The Pt/CZO catalystcalcined at 750 & DEG;C (Pt/CZO-750) exhibited a surprisingly higherC(3)H(8) oxidation activity than that calcined at550 & DEG;C (Pt/CZO-550). Through systematic characterizations andreaction mechanism study, it was revealed that the higher concentrationof surface Ce3+ species/oxygen vacancies and the strongerPt-CeO2 interaction on Pt/CZO-750 could better facilitatethe activation of oxygen to oxidize C3H8 intoreactive carbonate/carboxyl species and further promote the transformationof these intermediates into gaseous CO2. The Pt/CZO-750catalyst can be a potential candidate for the catalytic removal ofhydrocarbons from vehicle exhaust.