| AVS 55th International Symposium & Exhibition | |
| Graphene Topical Conference | Tuesday Sessions |
| Session GR+TF+NC-TuA |
| Session: | Graphene: Characterization, Properties, and Application |
| Presenter: | L. Goux, University of Texas at Dallas |
| Authors: | L. Goux, University of Texas at Dallas R. Guzman, University of Texas at Dallas J.-F. Veyan, University of Texas at Dallas Y.J. Chabal, University of Texas at Dallas |
| Correspondent: | Click to Email |
Graphene oxide (GO) is being investigated by the graphene community because it represents one of the most promising ways to produce graphene single sheets on a large scale.1,2 Indeed graphene oxidation followed by exfoliation and reduction has been recently demonstrated to give single graphene layers in solution3. In addition, in any practical electronic device systems, electron transporting materials need to be controlled by insulating materials which can function as gate dielectrics or separator between device structures. Thus, the role of GO in graphene-based nanoelectronics may be comparable to that of SiO2 in silicon-based microelectronics. We have therefore developed in-situ IR characterization to monitor graphene oxidation and GO reduction, in order to facilitate the development of graphene-based nanoelectronics. Graphene oxidation is being achieved using a remote oxygen plasma generator. We have designed a vacuum IR-cell (10-7 Torr base pressure), connected to the oxygen plasma and a Nicolet 6700 FT-IR spectrometer. Preliminary experiments have been carried out using HOPG. The GO reduction is performed in-situ by high temperature annealing in a Specac high temperature cell. In-situ FTIR studies of GO upon thermal reduction have shown a production of CO2 gas concomitant with the disappearance of the vibrations associated to carboxyl, hydroxyl and peroxide groups in the 120°C-230°C temperature range. Interestingly the vibrational lineshape suggests that CO2 is incorporated in GO. Around 290°C, there is a strong increase of the absorbance associated with structure changes of GO, resulting from an increase in scattering due to a higher refractive index. The change of refractive index most likely arises from an increase of electrical conductivity after reduction of GO.
1Stankovich, S. et al. Carbon 45, 1558–1565 (2007).
2Stankovich, S. et al. J. Mater. Chem. 16, 155–158 (2006).
3Li, D. et al. Nature Nanotechnology 3, 101 - 105 (2007).