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

Abstract

We report on a simple and effective method of synthesizing graphene-like nanosheets on silicon substrates pre-deposited with a carbon film or carbon nanodots in hot-filament(HF)CVD from a methane precursor. The results of field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and micro-Raman spectroscopy (RS) indicate that the structure of graphene-like nanosheets is changed with the flow rate change of methane and the pretreatment of the substrate surface. The catalyst-free growth of graphene-like nanosheets is related to the diffusion and assembly of carbon atoms on the substrate surface and the separation of graphene-like nanosheets from the substrate surface.

Carbon nanoflake-nanoparticle interface: A comparative study on structure and photoluminescent properties of carbon nanoflakes synthesized on nanostructured gold and carbon by hot filament CVD

“…Figure 5 shows the Raman spectra of samples A-D. Each spectrum in this figure features the D, G, D', 2D, and D+G peaks, and the positions of these peaks are listed in Table 2. Among these peaks, the D, G, 2D, and D+G peaks are quite consistent with the characteristic Raman peaks of graphene flakes reported elsewhere [1,6,26,27], indicating that the synthesized nanomaterials are the graphite carbon nanoflakes. Table 2.…”

“…The peaks at ~ 1365 and 1610 cm -1 are the D and G peaks of amorphous carbon, and the peak at about 2123 cm -1 is related to the C-N bonds [25,26]. respectively.…”

“…Atomic hydrogen has a high chemical activity, so it easily reacts with CH 4 molecules absorbed on the carbon NPs and Au film and forms carbon atoms through the dehydrogenation reaction. Finally, these atoms form the graphite carbon layers on carbon NPs and Au NPs formed due to the melting of continuous Au film [19,26,35]. However, there are a great difference in the formation rate of graphite carbon layers on carbon and Au NPs.…”

Structure and photoluminescence of boron-doped carbon nanoflakes grown by hot filament chemical vapour deposition

“…Due to the etching of graphene by hydrogen plasmas, 28 the plasma was turned off during the growth of CNFs and BDCNFs. However, the ion bombardment can form micropits on the silicon substrate and improve the nucleation of carbon structures, 30 it is for this very reason that a plasma was employed during the growth of amorphous carbon nanodots.…”

Doping Effects and Grain Boundaries in Thermal CVD Graphene on Recrystallized Cu Foil

“…Yet graphene growth does not work on any substrate. At best, graphene‐like nanosheets of a complex structure are formed . Thus so far high quality growth has to be facilitated by a catalytic material.…”