High-resolution microscopy of carbon nanotubes

In this study, high-resolution lattice images of carbon nanotubes have been obtained from a JEOL 4000EX operating at 400kV. Using minimum dose techniques, the images were recorded as the tubes damaged rather quickly in the beam. Image simulations have been performed of graphite close to the {101̄0} or {112̄0} zone axes. The results show that the characteristic approx. 3.4 angstrom (0002) fringes seen in the nanotubes may still be observed from graphite planes that are tilted over by as much as 15°. The fine fringes have also been simulated by constructing a model of the nanotube. Again the results show that fine fringes may be observed even for tilted helical tubes. The facets formed in the end caps represent tilt grain boundaries. Possible structures for these boundaries will be discussed.