CVD synthesis of nitrogen doped carbon nanotubes using ferrocene/aniline mixtures

Nitrogen doped carbon nanotubes ( N- CNTs) have been synthesized by the chemical vapour deposition ( CVD). oating catalyst method using either 4- ferrocenylaniline or mixtures of varying concentrations of ferrocene/ aniline together with toluene as added carbon source. The N- CNTs produced are less stable ( thermal gravimetric analysis measurements), less graphitic and more disordered ( transmission electron microscope measurements) than their undoped counterparts. The ratio of the Raman D- and G- band intensities increase with the nitrogen concentration used during the CNT growth. Furthermore, the transmission electron microscope ( TEM) studies reveal that the CNTs are multi- walled ( MW), and that the diameters of the N- MWCNTs can be controlled by systematically varying the concentrations of the nitrogen source. The TEM analysis also revealed that when ferrocenylaniline and ferrocene/ aniline reactions are compared at similar Fe/ N ratios, higher N doping levels are achieved ( ca. 2 - 5 x) when ferrocenylaniline is the catalyst. (c) 2008 Elsevier B. V. All rights reserved.