K. Suenaga, C. Colliex, ^* N. Demoncy, A. Loiseau, H. Pascard, F. Willaime

Polyhedral and tubular graphitic nanoparticles made of carbon layers and boron nitride (BN) layers have been synthesized. These particles were observed in the soot collected on the anode deposit formed by arcing a hafnium diboride rod with graphite in a nitrogen atmosphere. Elemental profiles with subnanometer-scale resolution revealed a strong phase separation between BN layers and carbon layers along the radial direction. Most of these tubes have a sandwich structure with carbon layers both in the center and at the periphery, separated by a few BN layers. This structure provides insight into the atomistic mechanism of nanotube growth in the boron-carbon-nitrogen ternary system and may lead to the creation of nanostructured electronic devices relying on the controlled production of heteroatomic nanotubes.

K. Suenaga, Laboratoire de Physique des Solides, URA 002, Université de Paris-Sud, Bât. 510, 91405 Orsay, France.
C. Colliex, Laboratoire de Physique des Solides, URA 002, Université de Paris-Sud, Bât. 510, 91405 Orsay, France, and Laboratoire Aimé Cotton, UPR 3321, Campus d'Orsay, Bât. 505, 91405 Orsay, France.
N. Demoncy, Laboratoire des Solides Irradiés, CEA-CNRS, Ecole Polytechnique, 91128 Palaiseau Cédex, France, and Laboratoire de Physique des Solides, Office National d'Etudes et de Recherches Aérospatiales, BP 72, 92322 Châtillon, France.
A. Loiseau, Laboratoire de Physique des Solides, Office National d'Etudes et de Recherches Aérospatiales, BP 72, 92322 Châtillon, France.
H. Pascard, Laboratoire des Solides Irradiés, CEA-CNRS, Ecole Polytechnique, 91128 Palaiseau, France.
F. Willaime, Section de Recherches de Métallurgie Physique, CEA/Saclay, 91191 Gif-sur-Yvette, France.
^*   To whom correspondence should be addressed.