Substrate-Free Gas-Phase Synthesis of Graphene Sheets

Abstract

We present a novel method for synthesizing graphene sheets in the gas phase using a substrate-free, atmospheric-pressure microwave plasma reactor. Graphene sheets were synthesized by passing liquid ethanol droplets into an argon plasma. The graphene sheets were characterized by transmission electron microscopy, electron energy loss spectroscopy, Raman spectroscopy, and electron diffraction. We prove that graphene can be created without three-dimensional materials or substrates and demonstrate a possible avenue to the large-scale synthesis of graphene.

Ultrathin rhodium nanosheets

“…Analysis of the intensity profiles of electron diffraction patterns has been demonstrated to be a valid and important method for the accurate determination of the thickness of a graphene sheet 14 . For instance, in single-layered graphene the intensities of diffraction spots in the outer hexagons are comparable to those in the inner hexagons, whereas for multilayers the diffraction spots in the outer hexagons are more intense 15 .…”

Chemical functionalization of graphene oxide for improving mechanical and thermal properties of polyurethane composites

“…[ [5][6][7][8][9][10] To obtain defect-free, high-quality graphene sheets, the most widely used approaches are chemical vapour deposition [11,12] and micromechanical cleavage of graphite [13]. Still, these approaches show a low production yield and are time consuming.…”

The Preparation of Alumina Particles Wrapped in Few-layer Graphene Sheets and Their Application to Dye-sensitized Solar Cells

“…15 The D band is due to the breathing modes of sp 2 atoms in rings. In general, the D band, which has often been observed for graphene sheets prepared by chemical reactions, [26][27][28] is related to the occurrence of defects and structural disorder in graphene sheets. 25 The G band corresponds to the E 2g phonon at the Brillouin zone center.…”

“…The main preparation methods reported so far are micromechanical cleavage of bulk graphite, 1,2 graphite oxidation-exfoliation-reduction, 4-9 ultrahigh vacuum graphization of silicon carbide, 10,11 plasma enhanced chemical vapor deposition using methane as the carbon source, 12 and substrate-free gas-phase synthesis using a microwave plasma reactor. 13 In recent years, we prepared graphene sheets by the reduction of CO by aluminum sulfide (Al 2 S 3 ). 14,15 In this present work, we show another method for synthesis of graphene sheets by using CO gas which is reduced by aluminum nitride (AlN) powders.…”