| Abstract
| - Films of multiwall carbon nanotubes (MWCNTs) grown by thermal chemical vapor deposition were studiedusing small-angle X-ray scattering (SAXS). We assessed the extent of alignment of carbon nanotubes (CNTs)by examining relative SAXS intensities as a function of azimuthal angle. We also identified features in theSAXS patterns that correspond well to CNT diameters measured through high-resolution transmission electronmicroscopy. For the case of thick films, corresponding to CNTs with lengths on the order of a millimeter, wewere able to study the morphology of the films as a function of distance from the catalyst substrate. Weexamined two different films in which the morphologies of CNTs range from vertically aligned to entangledand tortuous. We determined that the alignment of CNTs as well as their average diameter can vary significantlythroughout the film, demonstrating the utility of SAXS for quantitative structural analysis of CNT films,indicating the potential to reveal new information about the CNT growth process, and relating variations inmorphology to evolution of the catalyst and reaction conditions.
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