Multi‐walled carbon nanotubes (CNTs) and nitrogen‐doped carbon (CNx) nanotubes have been synthesized by the aerosol‐assisted chemical vapour deposition (CVD) method. The samples were prepared from toluene and acetonitrile taken in different proportion. The structure of CNTs and CNx nanotubes was compared using first‐ and second‐order Raman spectra. The disorder‐induced D band was found to up‐shift with increase of the acetonitrile fraction. The ID/IG and IG′/IG ratios showed the opposite dependence on the doping level of CNTs. Both kinds of the substitute nitrogen: graphitic‐like and pyridinic‐like contribute to the disorder in CNx nanotube layers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Nitrogen-containing carbon nanotubes were obtained by pyrolysis of acetonitrile (CH 3 CN) at 850 °C over catalytic nanoparticles formed by the thermal decomposition of Co and Ni bimaleates or their mutual solutions. Structure and composition of synthesized samples were studied by electron microscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It is found that the yield of the nanotubes, the quality of the layer packing, and nitrogen content in the CN x nanotubes depend on the catalyst composition. XPS of the N 1s spectra show that nitrogen atoms are in two different electronic states in the carbon nanotubes. According to quantum chemical calculations these states can be ascribed to nitrogen atoms substituting for carbon atoms in the graphite network and pyridine-like atoms. It was shown that the nanotubes synthesized using catalyst with the ratio Ni/Co 1:1 contain the greatest proportion of pyridine-like nitrogen.

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