Ab initio density functional theory investigation of Structural and electronic properties of double-wall zinc oxide nanotubes

The electronic properties of double-wall zinc oxide nanotubes (DWZnONTs) are investigated via density functional theory. The DWZnONTs are separated into two categories¸ where the inner and outer nanotubes are armchair-armchair and zigzag-zigzag single-wall nanotubes. The band structure of the DWZnONTs is calculated. Our results show that the inter-wall coupling diminishes the energy gap in semiconducting nanotube. We found that the energy gap of DWZnONTs depends on the structure of the inner and outer walls.