Atmosphere treatment modulates metal-support interaction in Pt/CeO2 catalysts for efficient CO oxidation

Oxygen-enriched CO oxidation is a pivotal reaction in automotive exhaust and indoor air purification. Fine-tuning the active sites represents a significant challenge in this catalytic field. In this work, we modulated the chemical state of Pt on Pt/CeO 2 catalysts by varying pretreatment atmospheres (direct H 2 reduction and sequential O 2 calcination-H 2 reduction), then applied these catalysts to the CO oxidation reaction. It was found that the Pt/CeO 2 catalyst via direct H 2 reduction showed a much higher activity than the Pt/CeO 2 catalyst via sequential O 2 calcination-H 2 reduction. It was revealed that under O 2 -H 2 conditions, a strong metal-support interaction (MSI) introduced the highly dispersed small Pt clusters. Conversely, under H 2 reduction conditions, a moderate MSI causes the formation of larger Pt nanoparticles, exhibiting a significantly increased proportion of metallic states and promoting the activity of CO oxidation. This study provides an effective strategy for designing highly efficient catalysts.