Carbon nanocoils, due to their specula helical morphology, have been proven to be excellent field emission cathodes, which can be applied to the charging devices in electrophotography and direct-marking systems and also to the flat panel display devices. Nanocoils synthesized by chemical vapor deposition using Fe and indium tin oxide show a large distribution of the diameters and pitches of the nanocoils, witch affects the uniformity of their field emission. An improved method has been adopted to synthesize nanocoils by using an Fe-In-Sn-O composite catalyst, where each component is controlled accurately. The synthesized nanocoils show small diameters with small distribution. The measurement of the field emission current from the nanocoils shows the turn-on voltage as low as 30 V at the electrode gap of 130 μm, which is smaller than those of most carbon nanotubes and the previous nanocoil emitters. This is due to the decrease of the curvature radius of the emission sites. A lifetime test under the current density of 1 mA/cm2 shows that the nanocoil field emitter also has a good stability and long lifetime. These results indicate that the nanocoils are expected to be applied for the electron sources of high performance electron emission devices.
Yoshikazu Nakayama, Lujun Pan, Osamu Suekane, Toshikazu Nosaka, "Field Emission from Carbon Nanocoils Synthesized by Using Fe-In-Sn-O Composite Catalyst" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP19), 2003, pp 727 - 730, https://doi.org/10.2352/ISSN.2169-4451.2003.19.1.art00068_2