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Dynamic transformation between bilayer islands and dinuclear clusters of Cr oxide on Au(111) through environment and interface effects.

ABSTRACT: SignificanceFor oxide catalysts, it is important to elucidate and further control their atomic structures. In this work, well-defined CrO₂ bilayer islands and Cr₂O₇ dinuclear clusters have been grown on Au(111) and unambiguously identified by scanning tunneling microscopy and theoretical calculations. Upon cycled redox treatments, the two kinds of oxide nanostructures can be reversibly transformed. It is interesting to note that both Cr oxides do not exist in bulk but need to be stabilized by the metal surface and the specific environment. Our results suggest that both redox atmosphere and interface confinement effects can be used to construct an oxide nanostructure with the specific chemical state and structure.

SUBMITTER: Yi Z

PROVIDER: S-EPMC9295788 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Dynamic transformation between bilayer islands and dinuclear clusters of Cr oxide on Au(111) through environment and interface effects.

Yi Zhiyu Z Lin Le L Chang Yuan Y Luo Xuda X Gao Junfeng J Mu Rentao R Ning Yanxiao Y Fu Qiang Q Bao Xinhe X

Proceedings of the National Academy of Sciences of the United States of America 20220523 22

SignificanceFor oxide catalysts, it is important to elucidate and further control their atomic structures. In this work, well-defined CrO2 bilayer islands and Cr2O7 dinuclear clusters have been grown on Au(111) and unambiguously identified by scanning tunneling microscopy and theoretical calculations. Upon cycled redox treatments, the two kinds of oxide nanostructures can be reversibly transformed. It is interesting to note that both Cr oxides do not exist in bul ...[more]

PMID: 35605120

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