▎ 摘　　要

Graphene has shown great application prospects as an electrode material for supercapacitors. It is necessary to develop an industrially feasible method to produce a large amount of defect-free graphene. Here, graphite was exfoliated with high quality in a supercritical CO2 (scCO(2)) microemulsion containing 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][Tf2N]) coupled a self-developed jet impact to produce a dispersion of graphene nanosheets. The height of the graphene was about 70% of 3.5-5.5 nm, and the lateral size was about 70% of 700-1100 nm. After jet impact, the concentration increased by 5-8%, the thickness of the flakes was reduced by about 1 nm, and the lateral size was reduced by about 300 nm. The kinetic calculation proved that the jet impact could achieve the effect of secondary exfoliation. The obtained few-layer graphene could be applied to electrode materials of supercapacitors.