Enhanced Field Emission from Carbon Nanotubes Coated by Nanoparticles of Turbostratic Stacked Graphenes

Abstract

The field emission (FE) of the carbon nanotubes (CNTs) modified by hydrocarbon ion treatment with an energy of 80 eV has been demonstrated. Compared with untreated CNTs, the turn-on field and the threshold field of the modified CNTs decreased significantly. Scanning electron microscopy and transmission electron microscopy indicate that, after hydrocarbon ion treatment, the CNTs are coated by amorphous carbon layer at 300°C of substrate temperature and nanoparticles of graphene stacks at 700°C. It is considered that both amorphous carbon and stacked graphene coating layer can decrease the effective surface work function of CNTs and thus increase FE.