Field emission from single-wall carbon nanotube films

Abstract

We report on the field emission properties of single-wall carbon nanotube films, with emphasis on current–versus–voltage $\mathrm{(I–V)}$ characteristics and current stability. The films are excellent field emitters, yielding current densities higher than $\text{10\hspace{0.17em}}{\mathrm{mA\hspace{0.17em}cm}}^{\mathrm{-2}}$ with operating voltages that are far lower than for other film emitters, but show a significant degradation of their performances with time. The observed deviations from the Fowler-Nordheim behavior in the $\mathrm{I–V}$ characteristics point to the presence of a nonmetallic density of states at the tip of the nanotubes.