Decomposition of FeC catalyst particles in carbon nanofibers during TEM observation.

The effect of an electron beam on nanoparticles of two Fe carbide catalysts inside a carbon nanofiber was investigated in a transmission electron microscope. Electron beam exposure does not result in significant changes for cementite (θ-FeC). However, for Hägg carbide nanoparticles (χ-FeC), explosive decay is observed after exposure for 5-10 s.