Correlation of Fabrication and Structural/Electronic Properties of Carbon Nanotubes Using TEM/EELS

Abstract Since their discovery, carbon nanotubes have been the focus of much research effort aimed at optimizing growth conditions, elucidating physical structure, and measuring electronic properties. Measurement methods have included high resolution techniques such as AFM, STM, TEM, and EELS, as well as surface and bulk spectroscopic techniques, such as XPS. Most investigations have been quite specific, centering on a small number of nanotubes formed under particular growth conditions and typically employing only one or two modes of analysis. Broader, more systematic studies are relatively rare, and it is the intent of the present work to help fill this gap. We combine results of high-resolution TEM imaging, electron diffraction, low-energy EELS, and carbon K-edge EELS to characterize a variety of nanotube samples, grown and annealed under various conditions. The Carbon Nanotubes (Cnts) Are Made By The Dual, Pulsed-Laser Vaporization Method, And Purified With A Process That Involves Nitric Acid Reflux, Washing/Centrifugation Cycles, Hollow-Fiber, And Cross-Flow Filtration.