[en] Single-wall boron nitride nanotubes samples synthesized by laser vaporization of a hexagonal BN target under a nitrogen atmosphere are studied by UV and visible Raman spectroscopy. We show that resonant conditions are necessary for investigating phonon modes of BNNTs. Raman excitation in the UV (229 nm) provides preresonant conditions, allowing the identification of the A(1) tangential mode at 1370 cm(-1). This is 5 cm(-1) higher than the E-2g mode in bulk h-BN. Ab initio calculations show that the lower frequency of bulk h-BN with respect to large diameter nanotubes and the single sheet of h-BN is related to a softening of the sp2 bonds in the bulk due to interlayer interaction.
Disciplines :
Physics
Author, co-author :
Arenal, R.; Laboratoire d'Etudes des Microstructures, ONERA - CNRS / Materials Science Division, Argonne National Laboratory
Ferrari, A. C.; University of Cambridge > Department of Engineering
Reich, S.; University of Cambridge, Department of Engineering / Massachussets Institute of Technology, Department of Material Science and Technology
Wirtz, Ludger ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
Mevellec, J.-Y.; Institut des Materiaux Jean Rouxel, Laboratoire de Physique Cristalline
Lefrant, S.; Institut des Materiaux Jean Rouxel > Laboratoire de Physique Cristalline
Rubio, A.; Institut fuer Theoretische Physik, Freie Universität Berlin / European Theorical Spectroscopy Facility (ETSF)
Loiseau, A.; Institut fuer Theoretische Physik, Freie Universität Berlin / European Theorical Spectroscopy Facility (ETSF)
Language :
English
Title :
Raman spectroscopy of single-wall boron nitride nanotubes
Publication date :
2006
Journal title :
Nano Letters
ISSN :
1530-6992
Publisher :
American Chemical Society, Washington, United States - District of Columbia
