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Covalent Diamond-Graphite Bonding: Mechanism of Catalytic Transformation.

ABSTRACT: Aberration-corrected transmission electron microscopy of the atomic structure of diamond-graphite interface after Ni-induced catalytic transformation reveals graphitic planes bound covalently to the diamond in the upright orientation. The covalent attachment, together with a significant volume expansion of graphite transformed from diamond, gives rise to uniaxial stress that is released through plastic deformation. We propose a comprehensive model explaining the Ni-mediated transformation of diamond to graphite and covalent bonding at the interface as well as the mechanism of relaxation of uniaxial stress. We also explain the mechanism of electrical transport through the graphitized surface of diamond. The result may thus provide a foundation for the catalytically driven formation of graphene-diamond nanodevices.

SUBMITTER: Tulic S

PROVIDER: S-EPMC6482437 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Covalent Diamond-Graphite Bonding: Mechanism of Catalytic Transformation.

Tulić Semir S Waitz Thomas T Čaplovičová Mária M Habler Gerlinde G Varga Marián M Kotlár Mário M Vretenár Viliam V Romanyuk Oleksandr O Kromka Alexander A Rezek Bohuslav B Skákalová Viera V

ACS nano 20190326 4

Aberration-corrected transmission electron microscopy of the atomic structure of diamond-graphite interface after Ni-induced catalytic transformation reveals graphitic planes bound covalently to the diamond in the upright orientation. The covalent attachment, together with a significant volume expansion of graphite transformed from diamond, gives rise to uniaxial stress that is released through plastic deformation. We propose a comprehensive model explaining the Ni-mediated transformation of dia ...[more]

PMID: 30883098

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