Enhancement of electron field emission of nitrogenated carbon nanotubes on chlorination

Multi-wall nitrogenated carbon nanotubes (N-CNTs) are modified by the chlorine–plasma treatment (N-CNTs:Cl) and hence studied their field emission characteristics. It is observed that the turn-on voltage of N-CNTs is decreased from ~ 1.0 V/µm to ~ 0.875 V/µm on chlorination. The current density is enhanced from 1.3 mA/cm2 (N-CNTs) to ~ 15 mA/cm2 (N-CNTs:Cl) at an electric field of 1.9 V/µm. The X-ray absorption near edge structure spectra revels, the formation of different bonding of chlorine with carbon and nitrogen presence in the N-CNTs during the process of chlorine–plasma treatment by the charge transfer (or else) that increase the density of free charge carriers and hence enhanced the field emission characteristics of N-CNTs:Cl.