A First-principles study of Li adsorption and diffusion on graphene nanoflakes under the effect of external electric field as an anode material for Li-ion battery

In this work the interaction between Li ion and graphene surface with the absence and the presence ofexternal electric field (EEF) applied perpendicular to the surface was investigated. M06-2X/6-31G(d) DFT calculationswere performed to describe the adsorption and diffusion properties. Meaning of the binding energy and scanning thepotential energy surface (PES) of the charged molecular systems in the presence of EEF is different from that in theabsence of electric field as the binding energy is an anisotropic characteristic which depends on the orientation ofmolecules with respect to the EEF. With the electric field increased from 0.0 a.u to 0.02 a.u , the diffusion barriers weredecreased from 24 to 20 Kj/mol , for the Li ion in the graphene nanoflakes. We concluded that the external electric fieldcan increase the charging speed of rechargeable ion batteries based on the graphene anode materials.

کلیدواژه ها:

external electric field ، grapheme ، rechargeable ion batteries