Field emission property of N-doped aligned carbon nanotubes grown by pyrolysis of monoethanolamine

Densely distributed bamboo-shaped nitrogen-doped aligned carbon nanotubes, grown on silicon substrate by thermal decomposition of monoethanolamine/ferrocene mixtures at 900 ∘C, were investigated for field electron emission. The morphology and crystallinity of the as-grown carbon nanotubes were characterized by SEM, TEM and Raman spectroscopy. X-ray photoelectron spectroscopy was used to analyze the nitrogen concentration on carbon nanotubes and it was observed that nitrogen concentration on nanotubes was 6.6 at.%. Field emission study of as-grown nitrogen-doped carbon nanotubes suggests that they are good emitters with a turn-on and threshold field of 1.8 V/μm and 2.53 V/μm, respectively. The maximum current density was observed to be 6 mA/cm2 at 3 V/μm. It is considered that the nice field emission performance of CNx nanotube is due to the presence of lone pairs of electrons on nitrogen atom that supplies more electrons to the conduction band.