A computational study on the application of AlN nanotubes in Li-ion batteries

We investigated the potential application of the AlN nanotubes (AlNNTs) in Li-ion batteries by means of the density functional theory calculations. To this aim, the interaction of Li atom and Li+ cation with (3,3), (4,4), (5,5), (6,6), and (7,7) armchair AlNNTs was investigated. By decreasing the curvature of these nanotubes, the HOMO and LUMO levels are shifted to lower and higher energies, thereby enlarging the energy gap. It was found that AlNNTs can produce larger cell voltage in comparison to the carbon nanotubes and may be promising candidate for application in the anode electrode of Li-ion batteries. The calculated cell voltage is in the range of 1.66 to 1.84 V which is significantly increased by increasing the diameter of AlNNTs. The adsorptions of Li and Li+ on the exterior surface of AlNNTs are more favorable than those on its exterior surface. We showed that the interaction of atomic Li with the surface of the AlNNT plays the main rule in determining the cell voltage because of its large dependency on the tube diameter. While the interaction of Li+ is nearly independent of the tube diameter because of the electrostatic nature of the interaction.