Visible-Light-Activated CuFe₂O₄/Zn-BTC Photocatalyst for Efficient Mineralization and Detoxification of Carbofuran in Industrial Effluents

Growing concern over carbofuran (CBF) contamination present in water bodies has increased the need for effective remediation strategies. Herein, CuFe₂O₄ nanoparticles, Zn-BTC MOF (H₃BTC; 1,3,5-benzenetricarboxylic acid), and CuFe₂O₄/Zn-BTC composite were successfully synthesized and characterized using various analytical techniques to investigate physiochemical and electrochemical properties. These photocatalysts were subsequently employed for the CBF degradation in wastewater. The CuFe₂O₄/Zn-BTC composite degraded(96%) 20 mg/L CBF in 90 min under optimized conditions (0.01 g/L catalyst loading, 7 pH, and light intensity 50 W LED). The superoxide ions (·O₂⁻) and hydroxyl radicals (·OH) were identified as the main oxidants, due to the strong interaction between CuFe₂O₄ and Zn-BTC, which promoted the separation of electrons and holes and increased the number of reactive sites. The photocatalytic activity remained stable in five successive cycles with a slight decrease in efficiency from 96% to 91%. When exposed to real pesticide effluent, total organic carbon (TOC) was reduced 69% and chemical oxygen demand (COD) was reduced 77%. A near complete detoxification of CBF was confirmed by Escherichia coli assays and degradation intermediates were identified by LC-MS, and a plausible reaction pathway was suggested. The results indicate that CuFe₂O₄/Zn-BTC is stable and effective photocatalyst for the removal of CBF from contaminated water.