Tri-Metallic NiCoFe-Layered Double Hydroxide as a Multifunctional Electrocatalyst for Emerging Contaminant Removal from Industrial Wastewater

Industrial wastewater in Islamabad has led to serious environmental and human health impacts due to the release of endocrine-disrupting chemicals (EDCs) and volatile organic compounds (VOCs) in the water bodies. The advent of wastewater treatment technologies has led to the development of novel approaches like the use of an electrocatalyst for efficient and safe removal of toxic contaminants from the wastewater. In this study, an efficient tri-metallic NiCoFe2-LDH electrocatalyst was prepared by optimizing the metal ratios in the synthesis process using a co-precipitation method. The catalyst was characterized by various tools such as UV-visible spectroscopy, SEM, EDX, and FTIR. A three-electrode electrochemical system (counter, reference, and working electrodes) was used for electrocatalytic activity and simultaneous removal of EDCs from the wastewater. Wastewater samples were collected from selected locations along the industrial discharge channel (Nullah Lai) in the industrial zone of Islamabad city. The physio-chemical analysis showed significant water pollution, including EDCs, VOC, and heavy metals. The electrochemical treatment using NiCoFe2-LDH demonstrated high efficiency across different scan rates (5 to 50 mV/s) and voltages (−0.02 to 1.6 V); for instance, at 1.6 V, the current density rises from 10 mA/cm2 in Scan 5 to 50 mA/cm2 in Scan 50. Furthermore, COD levels were significantly reduced by 74.9%, from 665.6 mg/L to 166.4 mg/L, after electrochemical treatment with NiCoFe2-LDH. GCMS analysis of organics revealed that the electrochemical process was effective in reducing several EDC- and VOC-related peak groups. Overall, this study highlights the potential of the electrochemical approach for treating EDC-contaminated wastewater and its applicability as a sustainable solution for industrial wastewater treatment.