| Abstract
| - Field emission studies were conducted on as-produced CoMoCAT single-walled carbon nanotube/silicacomposites with controlled nanotube diameter and bundle size. It has been observed that the as-producednanotube material does not need to be separated from the high-surface area catalyst to be an effective electronemitter. By adjusting the catalytic synthesis conditions, single-walled carbon nanotubes (SWNT) of differentdiameters and bundle sizes were synthesized. A detailed characterization involving Raman spectroscopy,optical absorption (vis-NIR), SEM, and TEM was conducted to identify the nanotube species present in thedifferent samples. The synthesis reaction temperature was found to affect the nanotube diameter and bundlesize in opposite ways; that is, as the synthesis temperature increased the nanotube average diameter becamelarger, but the bundle size became smaller. A gradual and consistent reduction in the emission onset fieldwas observed as the synthesis temperature increased. It is suggested that the bundle size, more than thenanotube diameter or chirality, determines the field emission characteristics of these composites. This is aclear demonstration that field emission characteristics of SWNT can be controlled by the nanotube synthesisconditions.
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