Dopants as Morphology Promoters: a Fundamental Study of the Role of Boron and Sulfur in the Formation of MWNT Junctions

We have synthesized CNT-based hierarchical structures via an aerosol assisted CVD process. Our experiments consist of pyrolyzing a solution containing C and Fe sources together with small amounts of B and S sources (800-900C, Ar atmosphere). The resulting structures consist of micron-size fibers decorated with short multi-walled carbon nanotubes that resemble ``nanotentacles.'' The materials have been characterized by SEM, HRTEM, EELS, TGA, XRD, XPS and Raman spectroscopy. Finally, these materials have been tested for its possible application in batteries and supercapacitors.