Improved tensile strength of carbon fibers undergoing catalytic growth of carbon nanotubes on their surface

We demonstrate that the tensile strength of carbon fibers (CFs) can be increased by more than 14% by the catalytic growth of carbon nanotubes (CNTs) onto their surface. Repair to some of the damage incurred during the formation of catalyst nanoparticles, an increase in the carbon crystal size, and the formation of crosslinks of neighboring crystals by CNTs all occur during the chemical vapor deposition process, and are the main reasons for the improvement. The interfacial shear strength of the CFs is also shown to be significantly improved due to the CNTs grown on the CF surface.