ENHANCEMENT OF FIELD EMISSION CHARACTERISTICS IN ALIGNED MULTIWALLED CARBON NANOTUBES DUE TO 70 MeV Ni⁶⁺ ION IRRADIATION

Here we report the role of ion irradiation in the field emission characteristics of aligned multiwalled carbon nanotubes (MWNTs). Aligned MWNTs show improvement in field emission characteristics under low dose 70 Mev Ni⁶⁺ ion irradiation. But field emission current density reduces for the higher dose due to adsorption of amorphous carbon and melting as well damage of carbon nanotubes (CNTs). High resolution transmission electron microscopic (HRTEM) analysis has been carried out to find the morphological changes due to ion irradiation leading to modifications in field emission characteristics. At low dose formation of dangling bond, cross-linking between different layers, exposure of buried emission sites and reduction of mutual shielding are responsible for the enhancement in field emission characteristics.