Effect of AlN dimers on the electronic properties of graphene quantum dot: DFT investigations

Abstract

Tuning the electronic properties of engineered graphene quantum dots (GQDs) is used to produce nanoelectronic devices, which are important in many applications. Chemical doping is applied to give GQDs controllable electronic properties. As a model for GQDs, we considered a molecule with 7 benzene rings and a hydrogen atom at the end of each edge carbon atom (written as C24H12). We considered engineering electronic characteristics in a GQD by altering its geometrical pattern of aluminium nitride (AlN) dimers, and so we employed the density function theory (DFT) approach with B3LYP/6-31G level to study the GQD with and without different dopants of AlN dimers. Ortho, meta, and para position dimers of aluminum and nitrogen atoms are used in the making of the three types of AlN dimers. The electronic properties which including DOS resolution, total energies, HOMO and LUMO energies, Fermi level, bandgap, reactivity descriptors, and molecular electrostatic potential are considered. It has been determined that the presence of AlN dimers has a major impact on the bandgap of the GQD. Based on our findings, the electronic characteristics of GQD are affected not only by the number of GQD dimers present but also by the arrangement of AlN dimers within the GQD. By suitably doping AlN dimers, we can tune the bandgap of GQDs. These results contribute to a better understanding of how chemical doping modifies electronic properties of GQDs and inspires the development of nanodevices with enhanced electronic performance.

Keywords

• Graphene quantum dots
• AlN dimers
• Electronic properties
• DFT
• Bandgap