▎ 摘　　要

The luminescent capability of graphene quantum dots (GQDs) was investigated and compared with that of carbon nanodots (C-dots) obtained from the same functionalization process. It was found that the optical gain of GQDs is higher than that of C-dots due to their geometrical advantages such as larger surface area to volume ratio and smaller volume. Under optical excitation at 266 nm, lasing emission was observed from a Fabry-Perot cavity containing a mixture of GQDs and TiO2 nanoparticles dispersed inside ethanol.