Diameter-Modulated Multi-Walled Carbon Nanotubes Without Bamboo-Like Partitions: Growth, Structure and Deformation...

Periodically diameter-modulated stack-type-multi-walled carbon nanotubes are grown from Fe-Ga catalyst nanoparticles using palmitic acid as a carbon source. A model for their formation mechanism is proposed: stick-slip motion of a catalyst nanoparticle in the growing nanotube results in periodic changes of diameter and wall thickness, and formation of inner partitions is suppressed when the degree of supersaturation is low. In addition, behaviors of nanotubes in Joule heating, bending, and under a tensile load were observed in-situ by scanning electron microscopy using micro-manipurators.