Non-Contact Local Conductance Mapping of Individual Graphene Oxide Sheets during the Reduction Process.
We used electrostatic force microscopy (EFM) to investigate local conducting states of atomically thin individual graphene oxide (GO) sheets and monitor the spatial evolution of their conducting properties during the reduction process. Because of the thinness of the GO sheets and finite carrier density, the electric field is partially screened in the reduced GO, which is manifested in the EFM phase signals. We found inhomogeneous oxidation states in as-prepared GO sheets and followed the evolution of reduction process in the individual GO sheets during both thermal and chemical reduction. We also compared the EFM measurement results with simultaneous IV characteristics to assess correlations between two measurements.
Department of Physics and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea.
Huiseong
H
Jeong
Department of Physics and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea.
Kyung Moon
KM
Lee
Department of Physics and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea.
Y H
YH
Ahn
Department of Physics and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea.
Soonil
S
Lee
Department of Physics and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea.
Ji-Yong
JY
Park
Conductance; Electrostatic Force Microscopy; Graphene Oxide; Reduction