Tailoring the Load Carrying Capacity of MWCNTs Through Inter-shell Atomic Bridging

Recent studies have finally produced accurate measurements of the mechanical properties of carbon nanotubes, confirming the anticipated results computed from quantum and molecular mechanics. Several studies have also predicted an enhancement of these material properties as a result of electron irradiation. Here we prove conclusively through a rigorous TEM imaging study that this enhancement occurs as a result of multiple-shell load transfer through irradiation-induced crosslinks. Using a computational model of the system which mirrors the experimental setup, we show that intershell covalent crosslinks resulting from the irradiation are efficient atomic structures for inter-shell load transfer. A study of the correlation between number of defects and load transfer provides insight into the experimental results and quantifies the increase in load transfer with radiation dose. The combined experimental/computational approach therefore gives a complete understanding of the phenomenon and provides the means for tailoring the mechanical properties of 1-D nanostructures.