14 Apr Mechanical Exfoliation
The mechanical exfoliation method was first described in 2008 in order to answer the needs for a scalable production method to produce graphene. Mechanical exfoliation is a top-down method that requires mechanical energy in order to exfoliate graphite.
Most commonly, techniques like sonication or high- shear-mixing are utilized. However, the efficiency of mechanical exfoliation is difficult to control. Consequently, this method usually leads to a large distribution of graphene flakes in size and thickness.
Graphene is a hydrophobic material, which is why additives or surfactants are required in order to obtain stable dispersions in polar solvents. Furthermore, many of the used surfactants or organic solvents can be toxic or harmful.
Even though this production method is simple enough, the quality and purity of the exfoliated graphene might not be sufficient for specific applications.