Simultaneous detection of heavy metal ions using MOF-derived zirconium oxide/porous carbon modified carbon paste electrodes

Toxic heavy metals are one of the most dangerous agents for the organism's health and the environment. In this study, a new, selective electrochemical sensor was prepared using zirconium oxide/porous carbon nanoparticles (ZrO2/NPC) modified carbon paste electrode for simultaneous determination of lead (Pb2+) and cadmium (Cd2+) ions. ZrO2/NPC material was obtained from one-step calcination of MOF. Infrared analysis and scanning electron microscopy were used to evaluate the characteristics of the sample and the prepared electrode. The electrochemical behavior of the modified electrode was evaluated using cyclic voltammetry in [Fe (CN)6]3-/4 solution, which represents the electron transfer process is controlled by diffusion, at the electrode surface. For quantitative analysis, differential pulse voltammetry method was used Under optimal analytical conditions, differential pulse voltammograms at different concentrations of Pb2 + and Cd2 + ions were recorded simultaneously by ZrO2 / NPC / CPE. and detection limits of 0.61 µM and 1.43 µM were calculated for Pb2+ and Cd2+ respectively. In addition, sensitivity, selectivity, and recovery were determined in real water samples.