Graphene, like graphite, is a two-dimensional material of hexagonal structure of carbon. With excellent properties such as high electrical conductivity, thermal conductivity and permeability, it has been widely applied in advanced science and technology fields including graphene composites, electronic materials and energy storage materials.
Several oxidation-reduction methods that are commercially available worldwide are suitable for mass production of graphene, but due to the nature of the processing procedure, many functional groups exist in the prepared graphene, resulting in crystalline defects. In addition, the use of a large amount of strong oxidizing agents causes environmental pollution and the effects of the prepared graphene or graphene oxide on the human body must be considered.
The method of directly obtaining graphene from graphite using shockwave in isopropanol has a disadvantage of low yield, but it is environmentally friendly and nontoxic, so it has a great research value.
Ju Yong Chol, a section head at the Institute of Nano Science and Technology, has prepared few-layer graphene by suspending graphite in isopropanol and applying shockwave generated during pulsed discharge to it, and investigated the effects of charging voltage, capacitor and number of discharges on the number of layers and yield of graphene.
The effects of charging voltage and capacitor on the number of layers of graphene are almost similar. The number of discharges plays an important role in the yield of graphene.
He has analyzed various properties of the graphene prepared using Optics microscope, X-ray diffraction and Raman spectroscopy, and confirmed the presence of 3-6 layer graphene. The yield of graphene is 8%.