Preparation of aqueous graphene suspensions by ultrasonication in the presence of a fluorine-containing surfactant

Concentrated suspensions of few-layer graphene particles have been prepared via natural graphite exfoliation by ultrasonic processing in the presence of a fluorine-containing surfactant and with no surfactant. The kinetics of the process and the properties of the products have been studied using laser diffraction, X-ray diffraction, transmission electron microscopy, electron diffraction, and Raman spectroscopy. We have obtained aqueous suspensions containing up to 95% few-layer graphene with a concentration of 6 mg/mL.