January 13, 2016

Nano-hybrid materials create magnetic effect

The calculated properties of a three-dimensional hybrid of graphene and boron nitride nanotubes
would have pseudomagnetic properties, according to researchers at Rice University and Montreal
Polytechnic. (Credit: Shahsavari Lab/Rice University)

(January 13, 2016)  Rice, Montreal Polytechnic study details electromagnetic properties of graphene-boron nitride materials 

Developing novel materials from the atoms up goes faster when some of the trial and error is eliminated. A new Rice University and Montreal Polytechnic study aims to do that for graphene and boron nitride hybrids.

Rice materials scientist Rouzbeh Shahsavari and Farzaneh Shayeganfar, a postdoctoral researcher at Montreal Polytechnic, designed computer simulations that combine graphene, the atom-thick form of carbon, with either carbon or boron nitride nanotubes.

Their hope is that such hybrids can leverage the best aspects of their constituent materials. Defining the properties of various combinations would simplify development for manufacturers who want to use these exotic materials in next-generation electronics. The researchers found not only electronic but also magnetic properties that could be useful.

Their results appear in the journal Carbon.

Shahsavari’s lab studies materials to see how they can be made more efficient, functional and environmentally friendly. They include macroscale materials like cement and ceramics as well as nanoscale hybrids with unique properties.

Researchers at Rice University and Montreal Polytechnic analyzed the electromagnetic effects
of junctions between nanotubes and graphene sheets. From top to bottom are a graphene/carbon
nanotube hybrid with seven-membered junctions, a graphene/carbon nanotube hybrid with
eight-membered junctions and a graphene/BNNT hybrid with eight-membered junctions.
(Credit: Shahsavari Lab/Rice University)

“Whether it’s on the macro- or microscale, if we can know specifically what a hybrid will do before anyone goes to the trouble of fabricating it, we can save cost and time and perhaps enable new properties not possible with any of the constituents,” Shahsavari said.

His lab’s computer models simulate how the intrinsic energies of atoms influence each other as they bond into molecules. For the new work, the researchers modeled hybrid structures of graphene and carbon nanotubes and of graphene and boron nitride nanotubes.

“We wanted to investigate and compare the electronic and potentially magnetic properties of different junction configurations, including their stability, electronic band gaps and charge transfer,” he said. “Then we designed three different nanostructures with different junction geometry.”

journal reference >>