Composite Nanostructures Based on Template-Grown Boron Nitride Nanotubules

The fabrication of boron nitride nanotubules and BN-based composite nanostructures within the pores of anodic aluminum oxide is described. Boron nitride nanotubules are produced by pyrolyzing 2,4,6-trichloroborazine over alumina templates at 750 °C. The nanotubules are polycrystalline, with crystallites exhibiting an orientational ordering such that the BN (001) planes are tilted 25° with respect to the tube axis. Nanotubules at least 20 μm long are observed, longer than what is expected for a growth mechanism that assumes a uniform substrate coating. This suggests that tubes grow in the axial direction faster than in the radial direction. As an example of a CVD-fabricated composite nanostructure, we synthesized coaxial C/BN/C nanotubules by the sequential pyrolysis of acetylene and trichloroborazine over alumina templates. BN-insulated copper nanowires were also fabricated by electrochemical deposition of copper into BN-coated templates.