Electrochemical sensor based on iron-based metal-organic framework nanocomposite derived from acid mine drainage for the detection of lead (II) ions in water

Lead (Pb 2+ ) in water poses significant health risks, which require sensitive and cost-effective detection techniques. This study addresses this challenge by presenting a novel electrochemical sensor based on Fe-alginate metal–organic framework (Fe-alg-MOF) composite. This composite was prepared by leveraging the high iron content in acid mine drainage (AMD) to form Fe-alg-MOF composite via an in situ synthesis process. Characterization revealed a semi-amorphous material with irregularly shaped Fe-MOF particles embedded within the alginate network, and a surface area of 302.4 m 2 /g. The Fe-alg-MOF was incorporated with polytetrafluoroethylene (PTFE) on a glassy carbon electrode (GCE) to fabricate a Fe-alg-MOF/PTFE/GCE sensor. Square wave voltammetry (SWV) was employed for Pb 2+ detection at − 0.59 V, achieving a detection limit of 1.0 µM and a linear range of 4–50 µM. Furthermore, the practical applicability of the sensor was demonstrated by high recovery rates (~ 100%) in real wastewater effluent samples. Compared to conventional sensors, this platform utilizes an AMD waste derived material, demonstrating significant potential as a cost-effective and reliable tool for monitoring lead contamination in environmental waters.