Electronic structure and field emission characteristics of a new kind of BeO nanotubes: A first-principles study

First-principles calculations are used to investigate electronic and field emission characteristics of (5, 5) capped BeO nanotubes (BeONTs), which indicate that their emission currents under external electric fields are close to those of carbon nanotubes, and decagons on their apexes are the most probable positions for electron emission. In addition, work functions of the (5, 5) BeONTs decrease linearly with applied electric fields. The remarkable influence of lithium adsorption on their field emission characteristics is also investigated. Their work functions decline distinctly after lithium adsorption, while the emission currents have been improved by more than one order of magnitude. Moreover, there is a polynomial relationship between the total currents and the external fields.