Carbon quantum dots from hemicucur[6]bit and the application for the detection of Pb²

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 Pb²⁺ in the light of the Resonance Rayleigh scattering (RRS) changes with the increasing Pb²⁺ concentration. The proposed probe emerges a high selectivity to Pb²⁺ 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 Pb²⁺ sensors, as well as the good anti-interference ability is confirmed by the specifical response to Pb²⁺ in the presence of other metal cations. Therefore, the proposed analysis of Pb²⁺ is explored for the application in real samples of tap water and lake water, in satisfied results of acceptable recoveries.