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RESEARCH PRODUCT

Photoluminescence of Carbon Dots Embedded in a SiO2 Matrix

Franco Mario GelardiMarco CannasFabrizio MessinaSimonpietro AgnelloLuisa SciortinoGianpiero Buscarino

subject

PhotoluminescenceMaterials sciencePhotoluminescent nanocarbonAnalytical chemistryNanoparticlechemistry.chemical_element02 engineering and technologyTrapping010402 general chemistry01 natural sciencesCarbon dots; Photoluminescent nanocarbons; Photoluminescent silica monolith; Time-resolved photoluminescence; Materials Science (all)Photoluminescence excitationMonolithgeographygeography.geographical_feature_categorybusiness.industryChromophore021001 nanoscience & nanotechnologyCarbon dot0104 chemical sciencesAmorphous solidchemistryOptoelectronicsPhotoluminescent silica monolithMaterials Science (all)0210 nano-technologybusinessCarbonTime-resolved photoluminescence

description

Abstract We synthetized carbon dots by a pyrolitic method, and studied their photoluminescence in aqueous environment and upon trapping in a solid matrix. To this aim, we devised a facile procedure allowing to embed the dots in amorphous SiO2, without the need of any pre-functionalization of the nanoparticles, and capable of yielding a brightly photoluminescent monolith. Experimental data reveal a remarkable similarity between the emission properties of carbon dots in water and in SiO2, suggesting that the chromophores responsible of the photoluminescence undergo only weak interactions with the environment. Time-resolved photoluminescence data reveal that the typical photoluminescence tunability of these dots mostly arises, in the present case, from the co-existence of two independent emission bands. These two signals have different emission peak positions (2.8-2.9 and 2.2-2.3 eV respectively) and decay lifetimes (7.0 and 9.0 ns respectively), while their intensity ratio is controlled by the excitation wavelength.

10.1016/j.matpr.2016.02.043http://hdl.handle.net/10447/179375