Characterization and Field Emission Properties of SWNTs and MWNTs

Carbon nanotubes have been rapidly recognized as one of the most promising electron field emitters ever since the first emission experiments reported in 1995, due to their unique structure and properties such as high aspect ratio, small radius of curvature at their tips, high mechanical strength and high chemical strength. In this paper, single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs) were characterized using scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. Electron field emission from these SWNTs and MWNTs was measured. The experimental results show that the field emission property of MWNTs is better than that of SWNTs. The field emission mechanisms were also discussed.