Electric Double Layer Capacitors Based on Porous Three-Dimensional Graphene Materials for Energy Storage

With the intensifying energy crisis, it is urgent to develop green and sustainable energy storage devices. Supercapacitors have attracted great attention for their extremely high power, ultra-long lifetime, low-cost maintenance, and absence of heavy metal elements. Electrode materials are the kernel of such devices, and graphenes are of great interest for use as electrodes for their tremendous potential. The three-dimensional (3D) network structure of graphenes have been recently highlighted as potential electrode materials of supercapacitors. In this review, supercapacitors based on the 3D graphene networks are surveyed in terms of aqueous and non-aqueous systems. The powdery and bulky 3D graphene materials are discussed for fabricating the electrodes. Lastly, challenges and perspectives of the graphene-based supercapacitors are presented.