Abstract
Abstract Electrochemical detection of toxic heavy metal ions is of great significance due to metals harmful impact on the environment. In this work, a reduced graphene oxide (RGO)-supported Ag/PANI nanocomposite electrochemical sensor was synthesized via oxidative polymerization for the detection of lead (Pb2+) and cadmium (Cd2+) ions in ground and surface water. The synthesized nanomaterials were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–Vis spectroscopy, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). The Ag/PANI/RGO-modified glassy carbon electrode (GCE) exhibited higher reversibility compared to other modified electrodes (PANI/GCE and PANI/RGO/GCE) at a scan rate of 50 mV/s, which is attributed to the synergistic interaction among PANI, RGO, and Ag nanoparticles on the electrode surface. Furthermore, the Ag/PANI/RGO nanocomposite sensor was evaluated using the anodic stripping voltammetry technique, yielding excellent linear regression coefficients (R2 = 0.9990 for Pb2+ and R2 = 0.9977 for Cd2+). Under optimized conditions, the Ag/PANI/RGO/GCE sensor demonstrated a wide dynamic linear range (10–100 µg/L), low detection limits (0.57 µg/L for Pb2+ and 0.78 µg/L for Cd2+), high sensitivity, and good recovery rates for the detection of heavy metals in water samples. Overall, the Ag/PANI/RGO/GCE-modified electrode shows strong potential as a reliable sensor for monitoring Pb2+ and Cd2+ contamination in ground and surface water. Graphical abstract