Tuning of chalcogenide nanoparticles fluorescence by Schiff bases

The interaction between chalcogenide (CdS and CdSe) nanoparticles and Schiff bases in the presence and absence of an electron withdrawing (nitro) substituent in organic media has been studied using steady-state and time-resolved fluorescence measurements. The changes in the chalcogenide nanoparticles luminescence properties in the presence of electron or hole acceptors provide information on their electronic properties. For this purpose, platelet-like chalcogenide nanoparticles with average size of ∼5–12 nm were synthesized using a simple microwave technique and characterized using UV–vis spectroscopy, XRD and TEM. The fluorescence quenching studies suggest that Schiff bases quench the fluorescence of chalcogenide nanoparticles effectively. Fluorescence lifetime studies suggest the presence of dynamic (collisional) encounters in the interaction of schiff bases with the chalcogenide nanoparticles. A possible quenching mechanism has also been proposed using Fourier transform infrared spectroscopy.