Structure and composition analysis of nanotubes and ceramics by a new 300 kV energy-filtered FEGTEM

A 300 kV energy-filtered transmission electron microscope equipped with an Omega-type energy filter has been developed for observation of high-spatial-resolution elemental images using inelastic electrons. The main characteristic features of the new microscope are described. The accelerating voltage dependence of the inelastic images is calculated to confirm that the spatial resolution for the elemental images is improved with an increase in the voltage from 120kV to 300 kV. It is shown that either homogeneous B-C-N or heterogeneous BN/C multi-walled nanotubes may be successfully distinguished on the elemental maps acquired at 300 kV. In addition, an atomic layer of oxygen atoms in Al11O3N9 crystal is well imaged as a bright line with a periodic separation of 2.9 nm along the c-axis. The spatial resolution for the oxygen maps is approximately 0.5 nm, that perfectly matches the theoretical calculations performed.