Production of graphene by exfoliation of graphite in a Taylor-Couette flow

Abstract

Production of graphene using a Taylor-Couette flow has been studied. Below, critical shear rate for exfoliation,shear force induced by rotating fluid and collision effect in turbulent vortex were effective to exfoliate graphite into graphene with few layers. By the analysis of transmission electron microscopy and atomic force microscopy, produced graphene has sub-micron size with less than 10 layers. Optimization of Taylor-Couette flow was performed for the operating parameters such as surfactant type, concentration, exfoliating time, initial graphite concentration, types of graphite for improved graphite exfoliation. As a result, high concentration of graphene dispersion up to 2.84mg/ml was achieved and highest yield was around 12%. We demonstrate that Taylor-Couette flow can be used to produce graphene. Taylor-Couette flow has a potential to exfoliate other kinds of materials with two-dimensional layered structure for mass production of two dimensional material with a few layers.