Band Gap Modulation of Graphene with Increasing Concentration of Li/B Doping

The paper reports the theoretical study of structural and electronic changes in single layer graphene sheet by replacing the carbon atoms with boron atoms and simultaneously adsorbing with equal amount of Lithium atoms. Ab-initio density functional theory calculations have been performed to investigate the effects of Boron-Lithium (Li/B) co-doping in graphene. Spanish Initiative for Electronic Simulation with thousands of atoms (SIESTA) and VASP codes were used for the calculation and results were compared. The combination of the hole (B) and electron (Li) doping effects, makes the Dirac point return to the original position. As a result of p–n co-doping at different concentrations, the electronic structures of graphene are modulated to open a band gap with width from 0.14 eV to 0.27 eV, depending on the co-doping concentrations. Thus, by adding equal amount of B and Li we can tune the band gap of graphene in required range which is beneficial for application of graphene in electronics.