Exfoliated Graphene Separated by Platinum Nanoparticles

Abstract

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 graphene morphology derived from drying aqueous dispersions of platinum nanoparticles adhered to graphene. Platinum nanoparticles with diameters spanning several nanometers 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 crystallites 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.