Field electron emission of the nanographite films consisting of few layer plate-like graphene crystallites (or nanowalls) and the films of entangled single-walled carbon nanotubes was investigated using scanning anode field emission microscopy. The surfaces of the films of both types were scanned with positively biased tip-anode in order to measure the distributions of properties of the individual emission sites in the film cathodes. The maximal emission currents and other characteristics of the cathodes were estimated using obtained data. The emission site distribution for the cathodes made from carbon nanotubes was found to be dependent on the nanotube film thickness. That was explained by the electrostatic screening effect. The comparative studies revealed a different behavior of the individual emission sites in nanotube and nanographite cathodes, which was assigned to the difference in mechanical properties of flexible tubes and rigid nanographite crystallites.
- Carbon Nanotubes
- Field Emission