Mapping defects in a carbon nanotube by momentum transfer dependent electron energy loss spectromicroscopy

Momentum resolved electron energy loss (EELS) spectra of multi-walled carbon nanotubes (MWCNT) have been measured at the C 1s edge in a transmission electron microscope (TEM). We demonstrate that structurally sensitive electron linear dichroic (ELD) signals analogous to X-ray linear dichroic (XLD) signals (Najafi et al., 2008) [17] can be measured by TEM-EELS from individual MWCNT if sample tilt and deflection of the inelastic scattering signal relative to the EELS spectrometer entrance aperture are used. This method is used to map defects in MWCNT at higher spatial resolution than is currently possible with X-ray microscopy.

► We show how to measure electron linear dichroism using TEM-EELS and sample tilt. ► We measure this electron linear dichroism (ELD) signal for a high quality MWCNT. ► We show the ELD is similar to that of X-ray linear dichroism (XLD). ► We measure ELD for a defective MWCNT. ► We present ELD-derived maps of the defects with 5 nm spatial sampling.