Theoretical Prediction and Low-cost Computational Screening of Functionalized Graphene Quantum Dots as Emerging...

In this study, we present a theoretical investigation of Graphene Quantum Dots (GQDs), a zero-dimensional derivative of two-dimensional graphene, as potential Förster Resonance Energy Transfer (FRET) probes. Using a cost-effective semi-empirical approach, we explore how surface functionalization with hydrogen (H), hydroxyl (-OH), and amino (-NH₂) groups systematically tunes the optical and electronic properties of GQDs. The passivation-dependent red-shifts observed in the emission spectra provide clear design rules for generating donor-acceptor pairs with strong spectral overlap. In particular, the yGQDs-rGQDs pair exhibits a Förster radius (R_o) of 6.47 nm, enabling efficient energy transfer over nanoscale distances. These results demonstrate that even simplified modeling can uncover fundamental trends in structure-property relationships of GQDs and predict their FRET performance with remarkable agreement to reported experimental spectra (< 5% error). Our findings highlight the potential of functionalized GQDs as versatile FRET probes and establish semi-empirical simulations as a practical screening tool for guiding the development of 2D material-derived fluorophores in biosensing and optoelectronic applications.