Single-walled carbon nanotubes (SWCNTs) are seamless cylindrical tubes consisting of carbon atoms with diameters ranging from less than one nanometer to a few nanometers. The arrangement of carbon atoms in a SWCNT is uniquely specified by using a pair of integers (n, m) referred to as the chiral indices. While the detailed structures, such as a carbon-carbon bond length, should be important, they have not been fully clarified yet. In this work, we examine the possibility of powder X-ray diffraction (XRD) method to characterize structures of SWCNTs. It is found that the XRD is a useful tool to "fingerprint" the chiral indices of bulk SWCNT samples. Besides, we find that information on the detailed structure within a SWCNT can be obtained from the XRD pattern. The application to a highly concentrated SWCNTs clarifies that the (6,5) SWCNT is expanded along the radial direction compared to that of ideal rolling up structure of graphene, with a negligible change along the tube axis. © 2014 Elsevier Ltd. All rights reserved.
Mitsuyama, R., Tadera, S., Kyakuno, H., Suzuki, R., Ishii, H., Nakai, Y., … Maniwa, Y. (2014). Chirality fingerprinting and geometrical determination of single-walled carbon nanotubes: Analysis of fine structure of X-ray diffraction pattern. Carbon, 75, 299–306. https://doi.org/10.1016/j.carbon.2014.04.006