Fig. 1. TEM image of GQDs (a), Fluorescence spectra of GQDs (b), and FTIR spectrum of GQDs (c)

Fig. 2. Displacement load curves of EP and GQDs/EP-x (x=1%, 2%, 3%) before (a) and after (b) gamma irradiation at 1 MGy; glass transition temperature of EP and GQDs/EP composites with 1% mass percentage of GQDs before and after 1 MGy gamma irradiation (c)

Fig. 3. FTIR spectra of EP and GQDs/EP composites with 1% mass percentage of GQDs before and after 1 MGy gamma irradiation

Fig. 4. XPSC1s spectra of EP and GQDs/EP composites with 1% mass percentage of GQDs before irradiation (a) and after (b) 1 MGy gamma irradiation

Fig. 5. EPR spectra of EP and GQDs/EP composites with 1% mass percentage of GQDs after 1 MGy gamma irradiation: (a) Gaussian magnetic field spectra; (b) g factor spectra