Boron nitride nanotubes composed of four- and eight-membered rings

Highlights: • Boron nitride nanotubes composed of four- and eight-membered rings is simulated and calculated in theory. • The band gap of the four-eight-membered rings BNNTs is 2.530–3.975 eV. • The band gap of four-eight-membered rings BNNTs decreases as the number of walls increases. - Abstract: The properties of boron nitride nanotubes composed of four- and eight-membered rings (referred to as four-eight-membered rings BNNTs) were calculated using density functional theory (DFT). The calculated results show that the band gap of the four-eight-membered rings BNNTs is greatly reduced, down to a range of 2.530–3.975 eV. The band gap decreases as the number of walls increases, not only enabling the allotropes to show semiconductor properties but also to fully meet the third-generation semiconductor band gap requirements, furthermore, the band gap decreases significantly with the number of walls increases.