Fig. 1. Fabrication of GQDs. (a) Schematic illustration of the synthesis process of GQDs. (b) TEM images of GQDs-7. (c) Absorption spectra of GQDs aqueous suspension with different reaction time (3 hours, 5 hours, and 7 hours). (d) UV-vis absorption spectra of pure GQDs-7. The inset was the photograph of dried GQDs-7.
