Carbon quantum dots from hemicucur[6]bit and the application for the detection of Pb.

A macrocyclic compound, hemicucurbit[6]uril (HemiQ[6]), is employed as the carbon source to produce a novel sort of carbon quantum dots (CQDs) with blue fluorescence in aqueous solution. The CQDs are fully identified by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Nuclear Magnetic Resonance (NMR), zeta potential, ultraviolet/visible (UV-vis) and photoluminescence spectroscopy (PL). The nanomaterial is developed for the analysis of Pb in the light of the Resonance Rayleigh scattering (RRS) changes with the increasing Pb concentration. The proposed probe emerges a high selectivity to Pb and excellent sensitivity in the linear concentration range of 0-6 μM with a detection limit low to 0.42 μM, which is superior to the previous values of Pb sensors, as well as the good anti-interference ability is confirmed by the specifical response to Pb in the presence of other metal cations. Therefore, the proposed analysis of Pb is explored for the application in real samples of tap water and lake water, in satisfied results of acceptable recoveries.