Graphene-based Materials*

Our top-down approaches [Lu et al.] inspired physicists to obtain graphene by micromechanical exfoliation. Another approach to individual layers involves converting graphite to graphite oxide (GO) to generate aqueous colloidal suspensions of `graphene oxide'(GO') sheets. (i) Reduced GO' (RGO') sheets were embedded in polymers such as polystyrene and their dispersion/morphology studied by SEM/TEM, and the conductivity/ percolation threshold of such composites was determined; (ii) individual GO' and RGO' sheets were studied to elucidate their chemical, optical, and electrical properties, (iii) GO' and RGO' sheets were embedded in thin glass films by a sol-gel route yielding conductive/transparent films, (iii) a `paper' material of stacked GO' sheets was made and characterized, (iv) powders composed of RGO' showed exceptional promise for use in ultracapacitors, and (v) C13-labeled GO was made and the detailed chemical structure of GO was determined with SS NMR.~ --Lu,Yu,Huang,Ruoff, ``Tailoring graphite with the goal of achieving single sheets'', Nanotechnology, 10, 269-272 (1999). See also http://bucky-central.me.utexas.edu/publications.htm 139, 146, 150, 155, 160, 164, 166, 168, 169, 174, 179-182, 184 where collaborators are shown as coauthors.