Charge distributions of Li-doped few-layer graphenes on C-terminated SiC surfaces

We performed first-principle density-functional theory calculations to study the charge distributions of Li-doped few-layer graphenes on C-terminated 6H-SiC (000 (1) over bar) surface. The charge transfer is investigated based on the electronic band structure and corresponding charge density difference. Furthermore, the values of transferred charges calculated by the Bader charge population scheme are given. It reveals that the graphene layers are all n-type doped. Most of the transferred charges reside on the bounding graphene layer between Li atom and graphenes and, only a few on the interior layers and substrate. It is found that the C-terminated SiC (000 (1) over bar) substrate supporting graphenes hardly influences the charge distribution of Li-doped graphenes. (C) 2011 Elsevier B.V. All rights reserved.