Design of 3D Graphene‐Oxide Spheres and Their Derived Hierarchical Porous Structures for High Performance Supercapacitors

Graphene‐oxide (GO) based porous structures are highly desirable for supercapacitors, as the charge storage and transfer can be enhanced by advancement in the synthesis. An effective route is presented of, first, synthesis of three‐dimensional (3D) assembly of GO sheets in a spherical architecture (GOS) by flash‐freezing of GO dispersion, and then development of hierarchical porous graphene (HPG) networks by facile thermal‐shock reduction of...