Carbon nanorods and graphene-like nanosheets by hot filament CVD: growth mechanisms and electron field emission

Abstract

Carbon nanorods and graphene-like nanosheets are catalytically synthesized in a hot filament chemical vapor deposition system with and without plasma enhancement, with gold used as a catalyst. The morphological and structural properties of the carbon nanorods and nanosheets are investigated by field-emission scanning electron microscopy, transmission electron microscopy and micro-Raman spectroscopy. It is found that carbon nanorods are formed when a CH 4 + H 2 + N 2 plasma is present while carbon nanosheets are formed in a methane environment without a plasma. The formation of carbon nanorods and carbon nanosheets are analyzed. The results suggest that the formation of carbon nanorods is primarily a precipitation process while the formation of carbon nanosheets is a complex process involving surfacecatalysis, surface diffusion and precipitation influenced by the Gibbs-Thomson effect. The electron field emission properties of the carbon nanorods and graphene-like nanosheets are measured under highvacuum; it is found that the carbon nanosheets have a lower field emission turn-on than the carbon nanorods. These results are important to improve the understanding of formation mechanisms of carbon nanomaterials and contribute to eventual applications of these structures in nanodevices.

Bimetallic Pd96Fe4 nanodendrites embedded in graphitic carbon nanosheets as highly efficient anode electrocatalysts

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Catalyst‐free Growth Mechanism and Structure of Graphene‐like Nanosheets Formed by Hot‐Filament CVD

“…In previous works, we synthesized graphene‐like nanosheets using a layer of gold film as a catalyst in HFCVD and found that graphene‐like nanosheets can be easily synthesized under a catalyst without plasma . In consideration of the future applications of graphene‐like nanosheets in biology, it is better to grow them free of catalyst .…”

Graphene-like carbon nanosheets prepared by a Fe-catalyzed glucose-blowing method for capacitive deionization

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