Fast, eco-friendly synthesis of blue luminescent nitrogen-doped graphene quantum dots in glycerol

Nitrogen-functionalized graphene quantum dots (N-GQDs) were synthesized by hydrothermal transformation of glycine precursors in glycerol. Functionalization of GQDs with nitrogen was confirmed with FTIR spectroscopy. Atomic force microscopy (AFM) analysis revealed that the thickness of the quantum dots is around ~ 1 nm while the lateral dimensions are in the range from 20 to 80 nm. N-GQDs exhibit strong fluorescence in the blue (420 nm) region and they are suitable for bioimaging applications.