  In graphene based materials, the energy storage capacity is usually improved
by rich porous structures with extremely high surface area. By utilizing
surface corrugations, this work shows an alternative strategy to activate
graphene materials for large capacitance. We demonstrate how to simply
fabricate such activated graphene and how these surface structures helped to
realize considerable specific capacitance (e.g., electrode capacitance of ~340
F g-1 at 5 mV s-1 and device capacitance of ~ 343 F g-1 at 1.7 A g-1) and power
performance (e.g., power density of 50 and 2500 W kg-1 at the energy density of
~10.7 and 1.53 Wh kg-1, respectively) in aqueous system, which are comparable
to and even better than those of highly activated graphene materials with
ultra-high surface area. This work demonstrates a new path to enhance the
capacity of carbon-based materials, which could be developed and combined with
other systems for various improved energy storage applications.
