Liquid Phase Production of Graphene by Exfoliation of Graphite in Surfactant/Water Solutions (original) (raw)

Hernandez et al 1 High yield production of graphene by liquid phase exfoliation of graphite

2016

Graphene is at the centre of nanotechnology research. In order to fully exploit its outstanding properties, a mass production method is necessary. Two main routes are possible: large-scale growth or large-scale exfoliation. Here, we demonstrate graphene dispersions with concentrations up to ~0.01 mg/ml by dispersion and exfoliation of graphite in organic solvents such as N-methylpyrrolidone. This occurs because the energy required to exfoliate graphene is balanced by the solvent-graphene interaction for solvents whose surface energy matches that of graphene. We confirm the presence of individual graphene sheets with yields of up to 12% by mass, using absorption spectroscopy, transmission electron microscopy and electron diffraction. The absence of defects or oxides is confirmed by X-ray photoelectron, infra-red and Raman spectroscopies. We can produce conductive, semi-transparent films and conductive composites. Solution processing of graphene opens up a whole range of potential large-scale applications from device or sensor fabrication to liquid phase chemistry.

Graphene produced with using surfactant from expanded graphite

Turkish Journal of Engineering, 2021

Graphene is a single layer of graphite with hexagonal structure which have stacked layers. Graphene has recently been recognized by its researchers due to it have sp2 bonds in hexagonal lattice, the two-dimensional structure of a single atomic thickness, and its superior electrical, electrochemical, optical, thermal, mechanical properties and lightness. Liquid phase exfoliation (LPE) is the most promising method of graphene research to produce high quality graphene in the production of single or low layer graphene layers. In addition, LPE is an easy and inexpensive method as well as enables the production of higher capacity graphene. LPE method in the production of graphene is the use of surfactant mainly to make water suitable as a means of exfoliation. Furthermore, graphene adsorbable surfactants provide an effective charge by electrostatic repulsion to prevent the re-aggregation of graphene sheets, thus providing stabilization against the recombination of suspended graphene layer...

High-yield production of graphene by liquid-phase exfoliation of graphite

Nature Nanotechnology, 2008

Graphene is at the centre of nanotechnology research. In order to fully exploit its outstanding properties, a mass production method is necessary. Two main routes are possible: large-scale growth or large-scale exfoliation. Here, we demonstrate graphene dispersions with concentrations up to ~0.01 mg/ml by dispersion and exfoliation of graphite in organic solvents such as N-methylpyrrolidone. This occurs because the energy required to exfoliate graphene is balanced by the solvent-graphene interaction for solvents whose surface energy matches that of graphene. We confirm the presence of individual graphene sheets with yields of up to 12% by mass, using absorption spectroscopy, transmission electron microscopy and electron diffraction. The absence of defects or oxides is confirmed by X-ray photoelectron, infra-red and Raman spectroscopies. We can produce conductive, semi-transparent films and conductive composites. Solution processing of graphene opens up a whole range of potential large-scale applications from device or sensor fabrication to liquid phase chemistry.