Luminescent properties of carbon nanodots bound to the surface of spherical microresonator

Hybrid structures were synthesized from monodisperse spherical silica particles, which are spherical microcavities, and emitting carbon nanodots on their surface. Carbon nanodots are attached to the surface of the particles by controlled coagulation in three solvents: ammonia, hydrochloric acid and glycerol. Intense narrow lines associated with the emission of nanodots in the whispering gallery modes of a spherical microcavity were observed in the photoluminescence spectra of hybrid structures over the entire radiation wavelength range of carbon nanodots from UV to near IR. All observed lines were identified by comparison with the spectral positions of the whispering gallery modes calculated by the method of spherical wave transfer matrices.