Lithium Adsorption on Armchair Graphene Nanoribbon: Insight from Theory

We have studied the adsorption of Li atoms at the hollow, bridge, and top sites of pristine armchair graphene nanoribbon using the density functional theory method. Li interacts with armchair nanoribbon through the charge transfer from Li, with binding energies per adatom of about 1.94eV, 0.93eV, and 0.74eV at hollow, bridge, and top sites, respectively. By Li adsorption, the Fermi level is shifted upwards in the conduction band due to the extra electrons that are achieved from donor Li atom. In the Li adsorption on the bridge and top sites, the band gap is larger than the Li adsorption on hollow site.