First-principles study of the oxygen adsorption and dissociation on graphene and nitrogen doped graphene for Li-air batteries

Recently, Yoo and Zhou [ACS Nano 5, 3020–3026 (2011)] reported that graphene can be directly used as electrode for Li-air batteries, suggesting that graphene itself can be served as catalyst for O2 dissociation reaction. In this work, we show from density functional theory calculations that the O2 dissociation reaction energy barrier is substantially decreased on the graphene surface comparing to that of in vacuum. Furthermore, N-doping can further decrease the energy barrier from 2.39 eV (undoped case) to 1.20 eV. The O2 molecule physical adsorption, O atom chemical adsorption at the graphene, and N-doped graphene surfaces are also simulated.