Revealing distortion of carbon nanotube walls via angle-resolved X-ray spectroscopy

Arrays of aligned single-walled carbon nanotubes (SWCNTs) produced by supergrowth method were studied by scanning electron microscopy (SEM) and angle-resolved near-edge X-ray absorption fine structure spectroscopy, which defined that nanotube disorder is 10-13 degrees and 23-27 degrees, respectively. The latter value was confirmed by X-ray fluorescent spectroscopy. The difference in the obtained angular deviations was attributed to distortion of the SWCNT walls, because the X-ray spectroscopy methods are sensitive to a local environment of probing atoms, while the SEM examines the nanotubes at a substantially larger length scale. Significant distortion (20-24 degrees) of SWCNT walls could be related to the defects introduced during the growth process. (C) 2015 Elsevier B.V. All rights reserved.