Electrical and thermoelectric transport by variable range hopping in reduced graphene oxide
Journal article, 2017
This study investigated the transport properties of single-layer reduced graphene oxides (rGOs). The rGOs were prepared by the bubble deposition method followed by thermal reduction. The crossover of the transport mechanism from Efros-Shklovskii (ES) variable range hopping (VRH) between the localized states to Mott-VRH was observed near 70K using the temperature-dependent conductance. The ES-VRH conduction below 70K is apparent in the electric field dependence of the field-driven hopping transport in the high-electric field regime. We also figure out that the thermoelectric power is consistent with the 2D Mott VRH above 70K. We argue that the VRH conduction results from the topological disorders of rGO as confirmed by Raman spectroscopy. This infers that the average distance between defects is approximately 2.0 nm.
Author
M. Park
Korea Institute of Science and Technology (KITECH)
Seoul National University
S. J. Hong
University of Hanover
Kyung Ho Kim
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
H. Kang
Seoul National University
M. Lee
Seoul National University
D. H. Jeong
Seoul National University
YungWoo Park
Seoul National University
B. H. Kim
Incheon National University
Applied Physics Letters
0003-6951 (ISSN) 1077-3118 (eISSN)
Vol. 111 17 173103Subject Categories
Condensed Matter Physics
DOI
10.1063/1.4987021