Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation

Simanenko A, Kastenmeier M, Piliai L, Kosto Y, Skála T, Tsud N, Mehl S, Vorokhta M, Matolínová I, Lykhach Y, Libuda J (2023)

Publication Type: Journal article

Publication year: 2023

Journal

Book Volume: 11

Pages Range: 16659-16670

Journal Issue: 31

DOI: 10.1039/d3ta02507a

Abstract

The redox capacity of Pt-CeO2 catalysts for low-temperature CO oxidation has been investigated by means of near-ambient pressure X-ray photoelectron spectroscopy, synchrotron radiation photoelectron spectroscopy, and resonant photoemission spectroscopy. The well-defined model Pt-CeO2 systems containing specific Pt species which differ with respect to the oxidation state, chemical environment, and nuclearity, including atomically dispersed Pt²⁺ and Pt⁴⁺ species, metallic Pt⁰ nanoparticles, ultra-small Pt* aggregates, and PtOx clusters were prepared by physical vapor co-deposition of Pt and Ce metals in an oxygen atmosphere onto a CeO2(111) buffer layer on Ru(0001) and subsequent annealing under reducing or oxidizing conditions. The oxidation states of Pt species and Ce cations were monitored upon CO exposure as a function of temperature. We found that metallic Pt⁰ nanoparticles, ultra-small Pt*/PtOx clusters, and Pt⁴⁺ species serve as CO adsorption sites at low temperature. Exclusively, the redox capacity for the low-temperature CO oxidation (below the room temperature) was observed only for the Pt-CeO2 catalyst containing metallic Pt⁰ nanoparticles. The corresponding redox pathway is associated with CO spillover and the formation of bidentate carbonate species. Above 400 K, the redox interaction of CO with model Pt-CeO2 catalysts involves the Mars-van Krevelen mechanism regardless of the nature of the Pt species.

Authors with CRIS profile

Involved external institutions

Univerzita Karlova v Praze / Charles University in Prague Czech Republic (CZ) Elettra Sincrotrone Trieste S.C.p.A. Italy (IT)

How to cite

APA:

Simanenko, A., Kastenmeier, M., Piliai, L., Kosto, Y., Skála, T., Tsud, N.,... Libuda, J. (2023). Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation. Journal of Materials Chemistry A, 11(31), 16659-16670. https://dx.doi.org/10.1039/d3ta02507a

MLA:

Simanenko, Alexander, et al. "Probing the redox capacity of Pt-CeO2 model catalyst for low-temperature CO oxidation." Journal of Materials Chemistry A 11.31 (2023): 16659-16670.

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