C-Dots/UiO-66-NH 2 -enhanced composite modified electrode for simultaneous detection of Pb 2+ and Cd 2+

Carbon dots and metal-organic frameworks (MOFs) have been widely used in a variety of applications such as sensing, energy storage, and catalysis, with fewer applications in electrochemical sensing. In this study, C-Dots/UiO-66-NH 2 was prepared as a modified material for glassy carbon electrodes for the detection of cadmium and lead ions in water by electrochemical methods (DPV) by selecting m-phenylenediamine as a source of carbon dots and amino-functionalized zirconium-based metal-organic frameworks, which are the combination of these two popular materials. Due to the complexation of amino groups with metal ions, a sufficient amount of amino groups provided a good interface for the adsorption of metal ions. Under the optimal deposition conditions, C-Dots/UiO-66-NH 2 exhibited good linearity and excellent detection limits for metal ions (Cd 2+ , Pb 2+ ) in the concentration range of 30 to 180 µg/L. The results showed that C-Dots/UiO-66-NH 2 was suitable for the determination of Cd 2+ and Pb 2+ in water. In addition, the C-Dots/UiO-66-NH 2 /GCE sensor has good immunity to interference and detection stability.