Realization of lasing emission from graphene quantum dots using titanium dioxide nanoparticles as light scatterers.

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 TiO(2) nanoparticles dispersed inside ethanol.