Near-edge X-ray absorption fine structure investigations of order in carbon nanotube-based systems

Probing order in nanotube systems is of fundamental importance in devising applications of these tubes in field emission applications as well as for components of composite materials. We use near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to qualitatively and quantitatively study the degree of order and alignment in a wide range of carbon nanotube-based systems, including single-walled carbon nanotube (SWNT) powder, SWNT films, and aligned multiwalled carbon nanotubes. The results are compared to analogous data obtained from a highly ordered pyrolytic graphite (HOPG) sample.