SYNTHESIS OF CARBON QUANTUM DOTS AND EUROPIUM-DOPED NANOMATERIALS FOR OPTICAL AND APPLICATIONS

Abstract

The invention and investigation of carbon quantum dots (CQDs) and europium-doped CQDs (Eu-CQDs) for advanced optical applications is the main goal of the present investigation. Through an elementary hydrothermal procedure, we successfully managed to develop exceptionally fluorescent nanoparticles using citric acid and ethylenediamine as precursors. The incorporation of europium ions (Eu³⁺) into the carbon matrix was carefully studied. Coordination with surface oxygen functional groups has been the primary approach for successfully incorporating Eu2+, and extensive examination using TEM, XRD, FTIR, and XPS validated the emergence of graphitic small particles. The Eu-CQDs revealed a unique dual-emissive operation that combines the vibrant, distinctive red emission of Eu³⁺ ions with the broad, tunable fluorescence of CQDs, as determined by preliminary optical investigation employing UV-Vis and photoluminescence spectroscopy. The real "antenna effect," which receives light and distributes energy to the Eu³⁺ ions via the CQD host, provides this synergy and significantly improves the luminescence of the ions. The potential advantages of these nanomaterials have been established by prototype applications in solid-state lighting (LEDs), bioimaging, and sensitive tetracycline antibiotic detection. Eu-CQD hybrids are adaptable and promising materials for environmental sensing, next-generation optoelectronic devices, and biomedical technologies, based upon the results.