Photoluminescence enhancement of carbon dots by Ag nanoparticles in thin-film hybrid structures

The plasmon enhancement of carbon dots (CDs) photoluminescence (PL) in thin-film structures with metal nanoparticles is of interest in their practical applications in sensors and light-emitters. This paper investigates CDs in the thin-film structures with nanogranulated silver films with different thickness. CDs in an aqueous solution were precipitated by spin-coating over the surface of annealed Ag films coated previously by a polymer layer. The IR, optical density and PL spectra of free-CDs and in thin-film structures with Ag films were studied. The PL intensity enhancement of CDs was demonstrated in the thin-film structures with Ag films due to absorption cross-section enhancement and the action of the Purcell effect. The improvement of thin-film structures producing technology will contribute to PL enhancement of CDs and the development of new thin-film sensors, light-emitters and other devices on their base.