Vol. 7, Issue 2, Part E (2025)

Graphene quantum dots (GQDs) have emerged as promising nanomaterials due to their exceptional electronic and optical characteristics; however, the precise modulation of their band gap and charge transport properties remains a persistent challenge. In this study, density functional theory (DFT) calculations were conducted to systematically investigate the impact of FeO dimer doping on the electronic and optical properties of GQDs. The results reveal that FeO doping significantly narrows the band gap from 4.130 eV to as low as 1.113 eV a reduction of up to 73.06% thereby enhancing the material's electronic conductivity. Molecular electrostatic potential (MEP) analyses demonstrate substantial charge redistribution induced by doping, suggesting improved reactivity and polarization. Moreover, simulated optical absorption spectra exhibit a pronounced redshift, expanding the absorption range from the ultraviolet to visible and infrared regions. These findings underscore the potential of FeO-doped GQDs as tunable nanostructures for advanced optoelectronic, sensing, and energy conversion applications. This work provides a theoretical foundation for the rational design of multifunctional carbon-based nanomaterials through targeted metal oxide functionalization.