Carbon Nanotubes and Graphene - Research and Applications

Researchers studied thoroughly the forces involved in repeatedly kinking and buckling a single multi-walled carbon nanotube (MWCNT) using an atomic force microscope (AFM) operating inside a transmission electron microscope (TEM). The measured forces were correlated to the geometry of the nanotube. The compressive force sustained by the nanotube was determined as a function of its deflection from the initial state. The results are in good agreement with the classical elastic theory of buckling. The Young’s modulus of the nanotube determined by this method is consistent with values obtained by other techniques. The researchers have tested the limits of the elasticity of the nanotube and found a lower bound on its yield strength of 1.7 GPa, which is higher than that of steel. After kinking, the plastic deformation of the MWCNT was also observed.