First-principles study on the enhancement of lithium storage capacity in boron doped graphene

The adsorption of Li ions on boron doped graphene was investigated using a first-principles method. Our results show that, as boron doping turns graphene into an electron-deficient system, more Li ions can be captured around boron doped centers than in pristine graphene. One boron atom doped into graphene (6C ring unit) can adsorb six Li ions, which indicates that boron doped graphene is an efficient Li-ion storage material for lithium batteries. Further investigations show that, under limited conditions, boron doped graphene (BC5) can form Li6BC5 compound after Li-ion adsorption, corresponding to a lithium storage capacity of 2271 mAh/g which is six times that of graphite.