Abstract

With reference to our recent reports [Appl. Phys. Lett. 90, 192107 (2007); Appl. Phys. Lett. 91, 202102 (2007)] about the electronic structure of chlorine treated and oxygen-plasma treated nitrogenatcd carbon nanotubes (N-CNTs), here we studied the electron field emission effects on chlorination (N-CNT:Cl) and oxidation (N-CNT:O) of N-CNT. A high current density (J) of 15.0 mA/cm(2) has been achieved on chlorination, whereas low J of 0.0052 mA/cm(2) is observed on oxidation compared to J=1.3 mA/cm(2) for untreated N-CNT at an applied electric field E-A of similar to 1.9 V/mu m. The turn-on electric field (E-TO) was similar to 0.875. The 1.25 V/mu m was achieved for N-CNT:C1 and N-CNT:O, respectively, with respect to E-TO= 1.0 V/mu n for untreated one. These findings are due to the formation of different bonds with carbon and nitrogen in the N-CNT during the process of chlorine (oxygen)-plasma treatment by the charge transfer, or else that changes the density of free charge carriers and hence enhances (reduces) the field emission properties of N-CNTs:C1 (N-CNTs:O). (C) 2008 American Institute of Physics. [DOI: 10. 1063/1.2981090]