부산대학교 도서관

Heavy metals such as cadmium (Cd), lead (Pb), mercury (Hg), and copper (Cu) are among the most toxic environmental pollutants due to their non-biodegradability, high toxicity, and major health-related risks. This study presents the implementation of electrochemical approaches to predict the selectivity of clay membranes towards heavy metal cations and explore their suitability for efficient water filtration. The clay membranes are processed into carbon paste electrodes (CPEs) and used as platforms for electrochemical assessments to investigate their selectivity towards the filtration of heavy metal cations, using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep anodic stripping voltammetry (LSASV). CV showed that Clay-CPE5@1000 °C (5 wt.% of clay) demonstrated the highest peak current. Furthermore, the Nyquist plot for Clay-CPE5@1000 °C exhibited the highest conductivity and enhanced charge transfer at the electrode/electrolyte interface. The selectivity of our proposed clay membrane followed the order of Pb2+ > Cu2+ > Hg2+ > Cd2+, according to the stripping currents in single-component systems. In a multi-component system, the Clay-CPE5@1000 °C electrode was found to be more selective towards Pb2+ and Cu2+ ions. Overall, these results proved the predictive capability of electrochemical approaches for heavy metal ion selectivity and demonstrated the potential of clay-based membranes for heavy metal cation filtration.