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Surface reduction properties of ceria-zirconia solid solutions: a first-principles study.

ABSTRACT: Based on the density functional theory (DFT), the reduction properties of Ce_1-x Zr _x O₂ (110) surfaces were systematically calculated using CO as a probe for thermodynamic study, and a large supercell was applied to build the whole composition range (x = 0.125, 0.250, 0.375, 0.500, 0.625, 0.750, 0.875). From the calculated energy barriers of CO oxidation by lattice oxygen, we found that composition Ce_0.875Zr_0.125O₂ exhibited the most promising catalytic effectiveness with the lowest activation energy of 0.899 eV. Moreover, the active surface O_3c ions coordinated by two Zr ions and one Ce ion were facilely released from their bulk positions than the O_3c ions surrounded by two Ce ions and one Zr ion on Ce_0.625Zr_0.375O₂, Ce_0.500Zr_0.500O₂, and Ce_0.375Zr_0.625O₂ (110) surfaces. This difference could be explained by the binding strength of O_3c with different neighboring cations.

SUBMITTER: Cao X

PROVIDER: S-EPMC9049197 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Surface reduction properties of ceria-zirconia solid solutions: a first-principles study.

Cao Xuesong X Zhang Chenxi C Wang Zehua Z Liu Wen W Sun Xiaomin X

RSC advances 20200128 8

Based on the density functional theory (DFT), the reduction properties of Ce1-x Zr x O2 (110) surfaces were systematically calculated using CO as a probe for thermodynamic study, and a large supercell was applied to build the whole composition range (x = 0.125, 0.250, 0.375, 0.500, 0.625, 0.750, 0.875). From the calculated energy barriers of CO oxidation by lattice oxygen, we found that composition Ce0.875Zr0.125O2< ...[more]

PMID: 35495250

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