Exfoliated Graphene Separated by Platinum Nanoparticles

Aggregation of isolated graphene sheets during drying graphene dispersions leads to a loss of its ultrahigh surface area advantage as a two-dimensional nanomaterial. We report a metal nanoparticle-graphene composite with a partially exfoliated grpahene morphology derived from drying aqueous dispersions of platimum nanoparticles adhered to graphene. Platinum nanoparticles with diameters spanning several nanomaters are adhered to graphene by a chemical route involving the reduction of metal precursors in a graphene dispersion. Face-to-face aggregation of graphene sheets is arrested by 3-4 nm fcc Pt cyrstallites on the graphene surfaces, and in the resulting jammed Pt-graphene composite, the Pt acts as spacers resulting in mechanically exfoliated, high-surface-area material of potential interest for supercapacitors and fuel cells.