Investigation of the Magnetic and Electronic Properties of Pyrrolic N-doped Graphene Using Density Functional Theory

Abstract

Modifying the bandgap and magnetic properties of graphene is one of the keys to realizing graphene-based nanodevices. Here, we investigate the effect of nitrogen concentration in the pyrrolic bond configuration on the magnetic properties of graphene using the spin-polarized Density Functional Theory (DFT) method. For a better understanding, we also calculated the electronic and structural properties of the pyrrolic N-doped graphene. This study used three models, i.e., pristine graphene and pyrrolic N-doped graphene with two nitrogen concentrations (N x G1 − x , x=2.000% and 3.125%). We observed that the higher the dopant concentration, the more the deformation of the planar structure in pyrrolic N-doped graphene. This is indicated by the more wrinkled structure that forms. Semi-metal to metal transitions were also observed in both models of pyrrolic N-doped graphene. Asymmetry behavior in the spin-polarized density of states (SPDOS) was also observed in both pyrrolic N-doped graphene models. The total magnetic moment increases with increasing dopant concentration. At a concentration of 2.000%, the resulting total magnetic moment is 1.68 µB/cell, and at a concentration of 3.125%, it is 1.74 µB/cell. We suggest that defects and nitrogen impurities play a crucial role in the transition of the magnetic properties of graphene. Our result shows that nitrogen-doped graphene with pyrrolic configuration is a promising candidate for nanomagnetic devices.