Stacking-Free Porous Graphene Network for High Capacitive Performance

Abstract

Reduced graphene oxide (rGO) composites for energy-related applications have attracted increasing attention. However, previous studies on rGOs still showed limitations because of unresolved several issues including p-p stacking between the graphene sheets, low wettability, and relatively high electrical resistance. Here, we report a fabrication method for a stacking-free porous graphene network (PGN) based on the intercalation of oxidized multiwall carbon nanotubes and graphitic carbon nitrides into partially exfoliated GO sheets with covalent sulfate bonding between each layer, followed by hydrothermal reduction to rGO. The three-dimensional PGN with high wettability and low electrical resistance provided a high capacitance of 338 F/g at 1 A/g, an outstanding energy density of 36.0 W h/kg at a power density of 1496.1 W/kg, and nearly 100% capacitance retention after 10,000 cycles. Our strategy overcomes the previous limitations of rGO and presents remarkable potential of 3D stacking-free rGO composites for practical energy-storage systems.