Root characterization of Fe-based catalyzed carbon nanotube forests

For the purpose of understanding the process of forming carbon nanotube forests catalyzed by Fe nanoparticles, a combination of ex-situ transmission electron microscopy observations and molecular dynamics simulation methods were used to study the rooting path of C in Fe and its motion evolution mechanism. The results show that C first reacts with Fe to form Fe3C, and C enters from Fe (110) crystal plane, thus Fe (110) crystal plane transferring to Fe3C (013) crystal plane; then C in Fe3C precipitates and grows into carbon nanotubes, and C precipitates from Fe3C (013) crystal plane, thus creating the relationship of the direction of carbon nanotubes growth parallel to Fe3C (013) crystal plane. The results of the microstructure snapshot over time and radial distribution function calculated by molecular dynamics simulation also show that the motion path of C is the same as the results deduced in the experiment, which confirms the correctness of the results.