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The production of concentrated dispersions of few-layer graphene by the direct exfoliation of graphite in organosilanes

Nanoscale Research Letters (Impact Factor: 2.52). 12/2012; 7(1):674. DOI: 10.1186/1556-276X-7-674
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ABSTRACT We report the formation and characterization of graphene dispersions in two organosilanes, 3-glycidoxypropyl trimethoxysilane (GPTMS) and phenyl triethoxysilane (PhTES) as new reactive solvents. The preparation method was mild and easy and does not produce any chemical modification. The dispersions, which exhibit the Tyndall effect, were characterized by TEM and Raman spectroscopy to confirm the presence of few-layer graphene. Concentrations as high as 0.66 and 8.00 mg/ml were found for PhTES and GPTMS, respectively. The latter is one of the highest values reported for a dispersion of graphene obtained by any method. This finding paves the way for the direct synthesis of polymer nanofiller-containing composites consisting of graphene and reactive silanes to be used in sol--gel synthesis, without any need for solvent removal, thus preventing graphene reaggregation to form graphite flakes.

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Available from: Valeria Alzari, Jan 13, 2014
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    • "This route is very simple and allows avoiding the use of special apparatuses and any chemical manipulation that might introduce defects in the exfoliated structures. Liquid exfoliation was successfully used to obtain high concentration of graphene in liquid solvents [23] [24] [25] [26] [27] and reactive compounds [28] [29] [30] [31] [32]; some of these were employed to synthesize polymer nanocomposites [25,27,28,30–32]. Similarly , tungsten disulfide can be exfoliated to give single and few http://dx.doi.org/10.1016/j.compscitech.2014.03.015 0266-3538/Ó 2014 Elsevier Ltd. "
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