Boron Nitride Characterized On A Nanometric Scale

The journal, Physical Review Letters, has published three articles that summarise the findings of the team. The last of these articles may be consulted in the new issue of the journal - number 98. The thorough control and knowledge of the properties boron nitride opens the door to the design of new materials based on this compound and, likewise, has implications in other fields such as biology.

Boron nitride (BN) is a binary compound of the element boron which consists of equal proportions of boron and nitrogen and is used for coatings in reactors and insulation materials. At a nano level, according to what Ángel Rubio’s group has been able to characterise, the compound has excellent electronic and mechanical properties such as high resistance, and can emit blue light, i.e. a wavelength shorter than red, thus augmenting storage capacity in applications for optoelectronic devices such as DVD, aerials and lasers. Moreover, it forms macroscopic structures (nanostructured molecular solids) through weak, van der Waals-type interactions, which, fundamentally, are in other fields of knowledge, particularly biology and supramolecular chemistry, where molecular self-assembly is dictated by these type of interactions.

The UPV/EHU team has shown, on the one hand, the role played by these weak (van der Waals-type) interactions in the stability of these BN nanostructures [1] and, on the other, the properties of absorption and emission of blue light and near ultraviolet [2], properties that are also the subject of this latest research [3]. The results are also relevant in the understanding of the properties of other carbon compounds (nanotubes, graphene) in fields such as nanoelectronics, photonics and materials for biomedical applications (sensors, biological labels, etc). All these fields are of great current scientific interest throughout the world and great advances are expected in the short and medium term.

Collaborating on this research with Ángel Rubio, who recently received the DuPont Science Award for his notable theoretical contributions to in the field of nanoscience and molecular nanotechnology, were doctors Ludger Wirtz, Andrea Marini, Jorge Serrano and Pablo García, as well as experimental teams from Japan and Grenoble.

[1] First-Principle Description of Correlation Effects in Layered Materials, A. Marini, P. García-González and A. Rubio, Physical Review Letters 96, 136404 - 4 (2006)

[2] Excitons in boron nitride nanotubes: dimensionality effects, L. Wirtz, A. Marini and A. Rubio, Physical Review Letters 96, 126104 - 4 (2006)

[3] Vibrational properties of Hexagonal Boron Nitride: Inelastic X-ray Scattering and ab initio Calculations, J. Serrano, A. Bosak, R. Arenal, M. Krisch, K. Watanabe, T. Taniguchi, H. Kanda, A. Rubio and L. Wirtz, Physical Review Letters 98, 095503 - 1,4 (2007)