Superior capacitive behaviors of the micron-sized porous graphene belts with high ratio of length to diameter

Abstract The construction of micron-sized porous graphene belts (PGBs) is realized by the chemical vapor deposition approach using porous MgO belts as substrates in the fluidized bed reactor. The as-obtained PGBs possess high ratio of length to diameter (up to 100), few-layered structure, large specific surface area and good structural integrity. The unique one-dimensional belt-like architecture with the large size contributes to inhibiting the restacking or aggregation for PGBs, therefore intrinsic outstanding properties of PGBs can be manifested. As electrode materials for the capacitive storage devices, the PGBs symmetric supercapacitor assembled with the aqueous electrolyte affords the much enhanced capacitance and higher capacitance retention in comparison with the commercial activated carbon. Besides, the Li ion capacitor fabricated with the Li 4 Ti 5 O 12 anode and PGBs cathode, exhibits satisfied Ragone performance (120 Wh kg −1 at 503 W kg −1 and 8044 W kg −1 at 51 Wh kg −1 ) and good durability. The superior capacitive behaviors of PGBs in aqueous and organic systems are ascribed to the synergistic effect of the one-dimensional robust belt-like microarchitecture and abundant pore channels.