| abstract |
Provided is a method of producing graphene-based supercapacitor electrode from a supply of coke or coal powder. The method comprises: (a) dispersing particles of the coke or coal powder in a liquid medium containing therein an optional surfactant or dispersing agent to produce a suspension or slurry, wherein the coke or coal powder is selected from petroleum coke, coal-derived coke, meso-phase coke, synthetic coke, leonardite, anthracite, lignite coal, bituminous coal, or natural coal mineral powder, or a combination thereof; (b) exposing the suspension or slurry to ultrasonication at an energy level for a sufficient length of time to produce a graphene suspension having isolated graphene sheets dispersed in the liquid medium; and (c) shaping and drying the graphene suspension into the supercapacitor electrode in a film, filament, rod, or tube form that is porous and has a specific surface area greater than 200 m 2 /g. |