First-principles analysis of electric field, spin–orbit coupling and lithium adsorption in graphene

Abstract

This study presents a first-principles examination of the effects of external electric fields (EEFs) on ion transport and adsorption processes in graphene. The Perdew--Burke--Ernzerhof (PBE) and local modified Becke--Johnson (lmBJ) exchange--correlation functionals, as implemented in WIEN2k, were used to investigate a 4 x 4 monolayer graphene supercell and lithium adsorption on graphene under electric fields ranging from 0.5 to 5 V/Å. The results indicate that the external electric field and spin--orbit coupling (SOC) modify the electronic structure of graphene, with lmBJ enhancing bandgap resolution. Lithium adsorption generated localised states, improved charge transfer and tuned the energy gap as the external field varied. The findings suggest that controlled electric fields can alter graphene's electronic properties, supporting possible developments in nanoelectronics and energy storage.