A detailed comparison of CVD grown and precursor based DWCNTs

Double-wall carbon nanotubes (DWCNTs) grown directly via a CVD method and DWCNTs produced by annealing C 60 and ferrocene filled single-wall carbon nanotubes were studied with X-ray, diffraction (XRD) and Raman spectroscopy. The samples showed the typical XRD patterns of hexagonally bundled tubes. The frequencies and linewidths of the inner tube radial breathing (RBMS) were (within experimental precision) equal in all three samples only the intensities differed. Finally, all samples showed the typical clustering of the inner tube RBMs due to the distribution of inner-outer tube pairs. The only difference was the population of specific inner-outer tube pairs where the CVD and ferrocene based DWCNTs were rather similar and both diffared from the C 60 based DWCNTs.