Electron-deficient Fe3O4@AC–NH2@Cu–MOF nanoparticles for enhanced degradation of electron-rich benzene derivatives via synergistic adsorption and catalytic oxidation

Abstract

Benzene derivatives in wastewater have negative impacts on ecosystems and human health, making their removal prior to discharge imperative. In this study, Fe₃O₄@AC–NH₂@Cu–opa (AC–NH₂ = aminoclay, Cu–opa = [Cu(opa)(bipy)_0.5(H₂O)]_n (H₂opa = 3-(4-oxypyridinium-1-yl) phthalic acid)) nanoparticles (NPs) were synthesized as adsorbent and catalyst for phenolic compound removal from wastewater. Fe₃O₄@AC–NH₂@Cu–opa NPs demonstrated outstanding performance in the adsorption of phenol, exhibiting a remarkable adsorption capacity of up to 166.39 mg g⁻¹ according to the Langmuir model. The composite also exhibited higher Fenton activity toward the degradation of electron-rich organic phenolic pollutants, with a rate approximately 3.4 times higher than that of Fe₃O₄ alone. The high catalytic activity of the composite was attributed to the large surface area and abundant active sites of the 2D charge-separated Cu–MOF. Meanwhile, the superparamagnetism of the Fe₃O₄ core enabled magnetic recollection and reuse without any significant loss of activity. Therefore, use of Fe₃O₄@AC–NH₂@Cu–opa/H₂O₂ shows potential in an efficient method for the removal of phenolic compounds from wastewater.