Electronic Transport in Composites of Graphite Oxide with Carbon Nanotubes

We show that the presence of electrically insulating graphite oxide (GO) within a single wall carbon nanotube network strongly enhances electrical conductivity, whereas reduced graphite oxide, even though electrically conductive, suppresses electrical conductivity within a composite network with single wall carbon nanotubes. Measurements of Young modulus and of Raman spectra strongly support our interpretation of the indirect role of the oxide groups, present in graphite oxide within the single wall carbon nanotubes/graphite oxide composite, through electronic doping of metallic single wall carbon nanotubes.