Multiwalled carbon nanotubes (MWNTs) prepared by carbon arc cathode deposit were characterized by scanning electron microscopy (SEM), high resolution transmission electron microcopy (HRTEM), X-ray diffraction (XRD), and nitrogen gas chromatography BET (Brunauer Emmett Teller) surface measurement. Experimental results indicate that besides carbon nanotubes, the as-received deposit also contains amorphous carbon particles, multi-layer polygonal particles (MPPs), and large graphite platelets. Various tube morphologies are revealed by phase contrast HRTEM images, which are probably associated with different catalyst behaviors involved in the tube growth. Within reasonable fluctuation range, fast Fourier transform (FFT) results and the XRD profile provide essentially identical structural information. The tube-containing deposit exhibits a broad pore size distribution range of 2-100 nm, which is consistent with its isotherm profile. (C) 2003 Elsevier B.V. All rights reserved.