(346h) Reduction of Freely-Suspended Crumpled Graphene Oxide Nanopaper

The reduction of freely suspended graphene oxide (GO) paper was investigated in a flow reactor configuration as a method for fast reduction of GO to graphene-like materials. Aerosolization of GO aqueous solution followed by rapid solvent evaporation produces stand-alone crumpled nanopaper-like sheets of about 150nm in size. Reduction of GO was conducted in a flow reactor with residence time of ~ 5 seconds in both air and argon environments. Reduced GO nanopaper was evaluated using X-ray photoemission spectroscopies (XPS) for chemical analysis, photoacoustic spectrometer for light absorption measurement, and cavity ring down method for optical extinction measurement. Online size selection and aerosol mass analysis was used to measure the mass loss of individual crumpled GO paper during reduction. The reduction kinetics from mass measurement was correlated with optical property characterizations. TEM images of reduced GO thin film indicated that the pre-crumpling of GO sheet contributes to the reduction in activation energy.