▎ 摘　　要

A pathway to open the band gap of graphene by p-n codoping is presented according to the first principles study. Two models are used: Lithium adsorbed on Boron-doped graphene (BC) and Boron-Nitrogen (B/N) codoping into graphene. The stability of Lithium adsorbed on BC is firstly analyzed, showing that the hollow site is the most stable configuration, and there is no energy barrier from some metastable configurations to a stable one. After the p-n codoping, the electronic structures of graphene are modulated to open a band gap with width from 0.0 eV to 0.49 eV, depending on the codoping configurations. The intrinsic physical mechanism responsible for the gap opening is the combination of the Boron atom acting as hole doping and Nitrogen (Lithium) as electron doping. (C) 2011 Elsevier B.V. All rights reserved.