High shear-induced exfoliation of graphite into high quality graphene by Taylor–Couette flow†
The development of an industrially scalable method to produce large quantities of high quality graphene is essential for its practical application in electronics, composite materials, and energy storage devices. Here, we report a method for bulk preparation of few-layer graphene by shear exfoliation of graphite in liquids. We showed that high shear mixing of graphite and solvent in the Taylor vortex flow regime resulted in an efficient exfoliation of graphite into few-layer graphene with a high yield. According to Raman spectroscopy and X-ray photoelectron spectroscopy, the exfoliated graphene flakes were found to exhibited a low oxidation degree and a low content of defects. Optimization of Taylor flow processing parameters based on computational fluid dynamics (CFD) studies further improved the efficiency of graphite exfoliation, thereby achieving an overall yield of up to ∼5%. The described Taylor flow-based shear exfoliation of graphite may have great potential to produce high quality graphene on an industrially accessible scale.