Abstract
The electrical properties of graphene doped with graphite and N-pyridine and their interaction with K+ ions have been studied using the density-functional based tight-binding (DFTB) method. Pure graphene and graphene with a single vacancy are used as comparisons. A 4 × 4 × 1 unit cell was used as the base, while an enlarged supercell consisting of primitive unit cells repeated to 40 × 40 × 1 was used for sampling. The structure and the Fermi Level of the optimized graphene agreed with the experimental data. The presence of N as a dopant in a graphitic configuration shifted the Fermi level to higher levels, while N in a pyridinic configuration shifted it to lower. Both showed an increase in the intensity of electronic activity. The presence of the dopant N resulted in the widening of the bandgap in graphene. The electrical characteristics of the examined graphenes influence the strength of the interaction with K+ ions.