Abstract The escalating global crises of hazardous waste accumulation and heavy metal contamination demand innovative solutions that simultaneously address environmental remediation and analytical sensing needs. This study presents a sustainable electrochemical platform fabricated from industrial and electronic waste streams for the high-performance detection of notorious heavy metals. Herein, we repurposed arc furnace dust into ferrite nanoparticles and converted spent battery graphite into highly conductive nitrogen-doped reduced graphene oxide (N-rGO) through controlled synthesis processes. The resulting Arc-ferrite/N-rGO nanocomposite was integrated into a carbon paste electrode, demonstrating exceptional electrochemical performance with a 3.5-fold increase in faradaic current and significantly improved electron transfer kinetics compared to bare electrodes. Through comprehensive optimization of differential pulse voltammetry parameters, the optimal conditions were established as follows: an acetate-KCl buffer (pH 4.5), a deposition potential of -1.1 V, a scan rate of 50 mV/s, and a 180 s accumulation time. The sensor achieved remarkable analytical performance for simultaneous detection of cadmium (II), lead (II), and mercury (II) with detection limits of 1.01 – 1.13 ppb, well below WHO guidelines for drinking water. Excellent linearity (R² > 0.995) across a 10.0 – 150.0 ppb concentration range and superior selectivity against a 100-fold excess of eleven common interfering cations demonstrated the sensor’s robustness for real-world applications. The sensor enabled the simultaneous detection of Pb²⁺, Cd²⁺, and Hg²⁺ in industrial wastewater, with results cross-validated by microwave plasma atomic emission spectroscopy. This work establishes a powerful circular economy paradigm, transforming environmental liabilities into valuable analytical assets while addressing the dual challenges of waste management and environmental monitoring. The Arc-ferrite/N-rGO sensor represents a scalable, economically viable, and environmentally responsible solution for next-generation heavy metal detection systems.
Reda et al. (2026) studied this question.