Fig. 2From: Synthesis of graphene quantum dots and their applications in drug delivery(reprinted/reproduced with the permission of Ref. [44], copyright 2015, RSC Advances)a UV–vis absorption spectrum of the GQDs at different excitation wavelengths. Inset: optical photograph of the GQDs dispersed in water under different wavelengths of irradiation. b PL spectra of the GQDs at excitation wavelengths from 260 to 580 nmBack to article page