Abstract
A pellet of as-grown multi-walled carbon nanotubes (MWNTs) prepared by compression was heat-treated at 3000°C for 30 min to eliminate metal impurities and a piece of the 3000°C-treated pellet was boron doped with a diffusion method. Electron energy loss (EEL) spectrum measurements for an individual boron-doped MWNT (B-MWNT) selected from the boron doped pellet were taken along the central line of the high resolution transmission electron microscope image, i.e. the line of the MWNT axis of the individual B-MWNT. Along the central line, a K-shell excitation EEL spectrum composed of two spectra, a weak boron K-shell excitation EEL spectrum and a strong carbon K-shell excitation EEL spectrum, was obtained at some positions, while at other positions only a carbon K-shell excitation EEL spectrum was recorded. Semi quantitative analysis of the energy loss near the edge structure of the boron K-edge revealed that boron doping had taken place quite locally in the individual B-MWNT.
