Modelling of NO Reduction on CeO₂-Supported Pt and Pd Nanoclusters

ABSTRACT

The reduction mechanism of NO to N₂ on CeO₂-supported Pt and Pd nanoclusters (Pt/CeO₂ and Pd/CeO₂) is analyzed using density functional theory. Different NO decomposition and N₂ formation pathways are evaluated, and the thermodynamically preferable paths are identified. The energy barrier of NO decomposition on Pt/CeO₂ indicates that the rate of reaction via metallic cluster sites and the ceria oxygen vacancies are comparable. In contrast, the cluster metallic sites of the Pd/CeO₂ induce a lower energy barrier of NO decomposition relative to the oxygen CeO₂ vacancy sites. The N₂ formation on the Pt/CeO₂ preferentially occurs via the N–N association, whereas the N₂O deoxidation is energetically preferred on the Pd/CeO₂.

KEYWORDS:

• NO reduction
• ceria-based catalysts
• platinum
• palladium
• density functional theory

Acknowledgements

The research reported in this work was funded by the Office of Sponsored Research at King Abdullah University of Science and Technology (KAUST) under the Competitive Research Grant OSR-CRG2018-3042.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the King Abdullah University of Science and Technology [OSR-CRG2018-3042].