A facile and scalable preparation of aqueous solutions of isolated, sparingly sulfonated graphene is reported. 13C NMR and FTIR spectra
indicate that the bulk of the oxygen-containing functional groups was removed from graphene oxide. The electrical conductivity of thin evaporated
films of graphene (1250 S/m) relative to similarly prepared graphite (6120 S/m) implies that an extended conjugated sp2 network is restored
in the water soluble graphene.