High-performance self-assembled graphene hydrogels prepared by chemical reduction of graphene oxide

Three-dimensional self-assembled graphene hydrogels (SGHs) have been fabricated by chemical reduction of graphene oxide (GO) with sodium ascorbate. The SGHs were characterized by scanning electron microscopy, rheological tests, electrical conductivity measurements, X-ray photoelectron spectroscopy. X-ray diffraction, and Raman spectroscopy. Results indicate that the reduction of GO promotes the assembly of graphene sheets. The SGHs are electrically conductive (1 S.m(-1)) and mechanically strong and exhibit excellent electrochemical performance. In 1 mol . L-1 aqueous solution of. H2SO4, the specific capacitance of SGHs was measured to be about 240 F.g(-1) at a discharge current density of 1.2 A.g(-1).