In situ observation of carbon nanotube nucleation process accompanied by catalyst particle dynamic morphology reconstruction is considered within a thermodynamic approach, and reveals the driving force for the liftoffa crucial event in the nanotube growth. A continuum model and detailed atomistic calculations identify the catalyst surface energy, affected by the chemisorbed carbon atoms at its exterior, and the emergence of a pristine high-energy facet under the sp2-carbon dome, as definitive factors for the liftoff. This further allows one to evaluate the range of chemical potential of feedstock, supporting the liftoff process, and provides insights on observed morphology oscillating behavior of the catalyst resulting into formation of multiwall carbon nanotubes.
Citation: Proceedings of the National Academy of Sciences of the United States of America-Physical Sciences
Pub Type: Journals
Nucleation of CNTs, In Situ ESTEM, modeling and atomistic calculations