| abstract |
Provided is a powder mass of multiple porous graphene balls, wherein at least one of the porous graphene balls comprises multiple graphene sheets having a catalyst, in a form of nanoparticles or coating having a diameter or thickness from 0.3 nm to 10 nm, bonded to or supported by graphene sheet surfaces, wherein the porous graphene balls have a density from 0.01 to 1.7 g/cm 3 (preferably and typically from 0.1 to 1.5 g/cm 3 ), and a specific surface area from 50 to 3,000 m 2 /g (preferably and typically from 200 to 2,630 m 2 /g). A method of producing such porous graphene balls is provided as well. Also provided is a gas storage device containing the invented powder mass as a gas-absorbing, gas-adsorbing, gas-capturing, or gas-storing medium to store a gas species therein. |