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Oxygen-Terminated (1 × 1) Reconstruction of Reduced Magnetite Fe₃O₄(111).

ABSTRACT: The (111) facet of magnetite (Fe₃O₄) has been studied extensively by experimental and theoretical methods, but controversy remains regarding the structure of its low-energy surface terminations. Using density functional theory (DFT) computations, we demonstrate three reconstructions that are more favorable than the accepted Fe_oct2 termination under reducing conditions. All three structures change the coordination of iron in the kagome Fe_oct1 layer to be tetrahedral. With atomically resolved microscopy techniques, we show that the termination that coexists with the Fe_tet1 termination consists of tetrahedral iron capped by 3-fold coordinated oxygen atoms. This structure explains the inert nature of the reduced patches.

SUBMITTER: Kraushofer F

PROVIDER: S-EPMC10084462 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Oxygen-Terminated (1 × 1) Reconstruction of Reduced Magnetite Fe3O4(111).

Kraushofer Florian F Meier Matthias M Jakub Zdeněk Z Hütner Johanna J Balajka Jan J Hulva Jan J Schmid Michael M Franchini Cesare C Diebold Ulrike U Parkinson Gareth S GS

The journal of physical chemistry letters 20230328 13

The (111) facet of magnetite (Fe3O4) has been studied extensively by experimental and theoretical methods, but controversy remains regarding the structure of its low-energy surface terminations. Using density functional theory (DFT) computations, we demonstrate three reconstructions that are more favorable than the accepted Feoct2 termination under reducing conditions. All three structures change the coordination of iron in the kagome Feoct1 layer to b ...[more]

PMID: 36976170

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