Synthesis and characterization of highly luminescent N-doped carbon quantum dots for metal ion sensing

ABSTRACTIn the present study, highly luminescent N-doped carbon quantum dots were synthesized by surface passivation of citric acid using Ethylenediamine. As synthesized NCQDs were characterized using different techniques as TEM, DLS zetasizer, UV-Visible spectroscopy and Photoluminescence spectroscopy. N-CQDs were found to have the approx 6.7 nm diameter and spherical shape as confirmed from TEM. UV-Vis absorption spectra at wavelength 350 nm (λmax = 350 nm) confirmed their formation in the solution. From photoluminescence spectroscopy, it was found these NCQDs emits at wavelength 450 nm ((λex = 350 nm, λem = 450 nm). As-synthesized N-doped CQDs were successfully used for fe3+ ion detection relying on the quenching mechanism.