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Updated: Jul 2, 2026

Simultaneous Synthesis of Single-walled Carbon Nanotubes and Graphene in a Magnetically-enhanced Arc Plasma
Published on: February 2, 2012
Chiral-angle distribution for separated single-walled carbon nanotubes
Yuta Sato1, Kazuhiro Yanagi, Yasumitsu Miyata
1Nanotube Research Center, National Institute of Advanced Industrial Science and Technology, and JST-CREST, Tsukuba 305-8565, Japan. yuta-sato@aist.go.jp
Abstract:
Chiral indices (n, m) of metallic and semiconducting single-walled carbon nanotubes (SWNTs) selectively separated via the density-gradient ultracentrifugation process were individually assigned by using an aberration-corrected transmission electron microscope (TEM) operated at 80 kV. Our statistical analysis revealed that armchair (n, n) and chiral (n, n-3) SWNTs with large chiral angles (>20 degrees) are dominant metallic nanotubes in the separated samples, whereas such a noticeable preference of particular indices was not observed for semiconducting nanotubes. Some significant discrepancies were found between the TEM and spectroscopic results on the major chiral indices and the metal/semiconductor ratios in these SWNTs.
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