Aug 27, 2009
Molecular dynamics predicts new boron nitride nanostructures
Carbon nanotubes (CNTs) are one of the most investigated structures in nanoscience and nanotechnology. From a topological point of view, CNTs can be considered as a sheet of graphite (also know as graphene) rolled up into a seamless cylinder. Single-walled and multi-walled CNTs exist. Related structures named carbon nanoscrolls also exist and have been produced experimentally.
Similarly, nanotubes and (in theory) nanoscrolls can also be formed from boron nitride (BN), which is an inorganic analog of graphite (hexagonal honeycomb-like lattice). Nanoscrolls, as shown in the picture above and accompanying videos, are structures formed by a two-dimensional sheet rolled up into a papyrus-like form.
Recently, Brazilian researchers have used molecular dynamics simulations to predict that BN nanoscrolls can exist as stable structures. CNTs and BN tubes have been produced experimentally by many groups, but up until now no clear evidence of BN nanoscrolls has been reported.
It is expected that BN nanoscrolls will also exhibit significant electroactuation, which is the phenomenon associated with mechanical deformation under charge injection. Also, in contrast to CNTs, the diameter of nanoscrolls can be varied easily (by contraction or by expansion), making them extremely radially flexible – a very useful property for hydrogen-storage applications.
Advances in the synthesis of two-dimensional BN sheets (single-layer BN has already been produced) brings the realization of BN nanoscrolls closer to reality. These remarkable nanostructures share some of the most useful properties exhibited by carbon nanotubes and nanoscrolls and present a selection of new ones. This opens up new and exciting opportunities in not just hydrogen storage, but also other areas such as nanoactuation.
The researchers presented their work in Nanotechnology.
About the author
Douglas S Galvao is professor at the Applied Physics Department of the State University of Campinas, São Paulo, Brazil. Eric Perim is a graduate student at the same department.