▎ 摘　　要

Ultrasonication is regarded as the most convenient and cleanest approach for graphene preparation from graphite. However, the yields are low in large scale preparation because after ultrasonication the exfoliated graphite is difficult to exfoliate into graphene, which leads to a great deal of waste. A new strategy for the efficient exfoliation of the exfoliated graphite into graphene was investigated by combining ultrasonication and grinding treatments. Results indicated that the exfoliated graphite produced by ultrasonication could be further exfoliated into graphene by combining ultrasonication and grinding. The obtained graphene sheets were all comprised of fewer than 10 layers with a yield of 4.73%. This was attributed to the destruction of the regular stacking of the graphite layers and scrolling and folding their edges to provide entry points for the solvent to overcome the interlayer forces between adjacent layers. This work provides a new strategy for the efficient exfoliation of graphite into few-defect graphene on a large scale.