Synthesis of graphene and carbon nanotubes hybrid nanostructures and their electrical properties.
The gapless semimetallic nature of graphene-based nanoelectronics is a major hurdle for the advancement of graphene-based field-effect transistors. Here graphene-carbon nanotubes hybrid nanostructures (Gr-CNTs HNSs) were formed by synthesizing single-walled carbon nanotubes (SWCNTs) with a bandgap on monolayer graphene by thermal chemical vapor deposition. We systematically established optimum conditions for the synthesis of Gr-CNTs HNSs by adjusting catalytic layer formation. The structural features of Gr-CNTs HNSs were investigated by scanning electron icroscopy and Raman spectroscopy. The surface morphologies and chemical states of the catlytic films used to optimize Gr-CNTs HNSs synthesis were explored by atomic force microscopy and X-ray photoelectron spectroscopy. In this process, graphene played a role as a barrier to prevent Fe nanoparticles from interdiffusing into Al2O3 layer. Based on these studies, we determined the catalytic structure (Fe/Graphene/Al2O3/SiO2) optimal for growing high-density SWCNTs on monolayer graphene. Electrical transport measurements revealed that Gr-CNTs HNSs exhibited p-type semiconducting behavior with combined properties of graphene and CNTs.
Department of Physics, BK21 Physics Research Division, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
Sang Hee
SH
Jung
Wooseok
W
Song
Su Il
SI
Lee
Yooseok
Y
Kim
Myung-Jun
MJ
Cha
Sung Hwan
SH
Kim
Dae Sung
DS
Jung
Min Wook
MW
Jung
Ki-Seok
KS
An
Chong-Yun
CY
Park