Electronic structure of octagonal boron nitride nanotubes

The effect of an octagonal lattice configuration on a boron nitride nanotube is explored using first principle calculations. Calculations show that the formational energy of an octagonal boron nitride nanotube (o-BNNT) is an exothermic reaction. Boron and nitrogen atoms within an o-BNNT have an average of 2.88 electrons and 9.09 electrons, respectively, indicating ionic-like bonding. In addition, the electronic structure of the octagonal boron nitride nanotube shows semiconductive properties, while h-BNNT is reported to be an insulator. Additional o-BNNTs with varying diameters are calculated where the results suggest that the diameter has an effect on the binding energy and bandgap of the o-BNNT. The defect sites of the o-BNNT are reactive against hydrogen where a boron defect is particularly reactive. Thus, this work suggests that physical and chemical properties of a boron nitride nanotube can be tailored and tuned by controlling the lattice configuration of the nanotube.