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Metal oxide nanoparticle growth on graphene via chemical activation with atomic oxygen.

ABSTRACT: Chemically interfacing the inert basal plane of graphene with other materials has limited the development of graphene-based catalysts, composite materials, and devices. Here, we overcome this limitation by chemically activating epitaxial graphene on SiC(0001) using atomic oxygen. Atomic oxygen produces epoxide groups on graphene, which act as reactive nucleation sites for zinc oxide nanoparticle growth using the atomic layer deposition precursor diethyl zinc. In particular, exposure of epoxidized graphene to diethyl zinc abstracts oxygen, creating mobile species that diffuse on the surface to form metal oxide clusters. This mechanism is corroborated with a combination of scanning probe microscopy, Raman spectroscopy, and density functional theory and can likely be generalized to a wide variety of related surface reactions on graphene.

SUBMITTER: Johns JE

PROVIDER: S-EPMC3883755 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Metal oxide nanoparticle growth on graphene via chemical activation with atomic oxygen.

Johns James E JE Alaboson Justice M P JM Patwardhan Sameer S Ryder Christopher R CR Schatz George C GC Hersam Mark C MC

Journal of the American Chemical Society 20131119 48

Chemically interfacing the inert basal plane of graphene with other materials has limited the development of graphene-based catalysts, composite materials, and devices. Here, we overcome this limitation by chemically activating epitaxial graphene on SiC(0001) using atomic oxygen. Atomic oxygen produces epoxide groups on graphene, which act as reactive nucleation sites for zinc oxide nanoparticle growth using the atomic layer deposition precursor diethyl zinc. In particular, exposure of epoxidize ...[more]

PMID: 24206242

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