A method of producing an aqueous dispersion of few-layer graphene nanosheets is disclosed, the method including: (a) mixing graphite particles with a perfluorosulfonate ionomer in an aqueous liquid, to form an aqueous dispersion of graphite particles; and (b) sonicating the aqueous dispersion of graphite particles to form an aqueous dispersion of few-layer graphene nanosheets, wherein the perfluorosulfonate ionomer is disposed as a thin and continuous layer on the few-layer graphene nanosheets. A composition is also disclosed, comprising an aqueous dispersion of a mixture of: (a) a perfluorosulfonate ionomer; and (b) a plurality of few-layer graphene nanosheets; wherein the perfluorosulfonate ionomer is disposed as a thin and continuous layer on the few-layer graphene nanosheets.