High-Yield High-Quality Graphene by exfoliation of graphite

Graphene sheets are prized for their unusual but exciting properties, including extremely high mechanical strength and ability to efficiently conduct heat and electricity. These properties open up a myriad of applications in medicine, electronics, energy, and sensors. However, the production of graphene, which is derived from the exfoliation of graphite, is currently challenged by low efficiency and long exfoliation times.

This invention uniquely combines two techniques, flow and sonication, to overcome these challenges. A graphite suspension is first subjected to a flow process, where it is mixed with zirconium oxide pebbles. Collisions between the graphite and the pebbles modify the graphite’s surface, making it easier for the solvent molecules to “wedge” in between layers during subsequent sonication, significantly increasing graphene exfoliation time-efficiency.

•       Graphene yield from graphite is quadrupled compared to traditional sonication-only treatment

•       Thin graphene sheets produced, between 1 and 3 layer thickness, compared to several nm thick with sonication-only treatment

•       Produces graphene with fewer topological defects

•       Enables continuous process to make graphene sheets from graphite

•      Touchscreens, LCDs, and OLEDs

•      Composites

•      Energy: PV cells and energy storage

•      Biosensors

•      Ultrafiltration