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Kinetic and Computational Studies of CO Oxidation and PROX on Cu/CeO₂ Nanospheres.

ABSTRACT: As supported CuO is well-known for low temperature activity, CuO/CeO₂ nanosphere catalysts were synthesized and tested for CO oxidation and preferential oxidation of CO (PROX) in excess H₂. For the first reaction, ignition was observed at 95 °C, whereas selective PROX occurred in a temperature window from 50 to 100 °C. The catalytic performance was independent of the initial oxidation state of the catalyst (CuO vs. Cu⁰), suggesting that the same active phase is formed under reaction conditions. Density functional modeling was applied to elucidate the intermediate steps of CO oxidation, as well as those of the comparably less feasible H₂ transformation. In the simulations, various Cu and vacancy sites were probed as reactive centers enabling specific pathways.

Supplementary information

The online version contains supplementary material available at 10.1007/s11244-023-01848-x.

SUBMITTER: Tangpakonsab P

PROVIDER: S-EPMC10505120 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Kinetic and Computational Studies of CO Oxidation and PROX on Cu/CeO2 Nanospheres.

Tangpakonsab Parinya P Genest Alexander A Yang Jingxia J Meral Ali A Zou Bingjie B Yigit Nevzat N Schwarz Sabine S Rupprechter Günther G

Topics in catalysis 20230731 15-16

As supported CuO is well-known for low temperature activity, CuO/CeO2 nanosphere catalysts were synthesized and tested for CO oxidation and preferential oxidation of CO (PROX) in excess H2. For the first reaction, ignition was observed at 95 °C, whereas selective PROX occurred in a temperature window from 50 to 100 °C. The catalytic performance was independent of the initial oxidation state of the catalyst (CuO vs. Cu0), suggesting that the same active phase is f ...[more]

PMID: 37724312

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