Preparation of graphene via liquid-phase exfoliation with high gravity technology from edge-oxidized graphite

摘要

In this paper, Rotating Packed Bed (RPB) is described to prepare graphene from edge-oxidized graphite (EOG). The concentration of graphene aqueous dispersion can reach 1.00 mg ml - 1 for a long time by the characterization of UV-visible spectrophotometer and the graphene aqueous dispersion can stabilize at room temperature for several months. Significantly, it is verified that the layer numbers of the graphene (R-GN) prepared by the new method is mostly 3-4 layers, the lateral size is double compared to that prepared by ultrasonic method (S-GN). Moreover, it has less defect, specific capacitance can reach 102 F g-1 at the sweep rate of 20 mV s(-1), and the capacitance retention hold 87% (after 10000 cycle numbers) at the sweep rate of 400 mV s(-1). These results indicate it is a green and efficient way to prepare graphene.