Adsorption and catalytic degradation by CoFe₂O₄ coated on metal–organic framework for the removal of 4-nitrophenol and 2,4-dichlorophenol

4-nitrophenol (4-NP) and 2,4-dichlorophenol (2,4-DCP) contaminated wastewater have attracted attention for their genotoxic and carcinogenic hazards. The magnetic MIL-101/CFO was constructed by synergistically integrating porous/hydrophilic/π-conjugated MIL-101(Cr) and CoFe₂O₄. The nanocomposites markedly accelerated the catalytic reaction activity. The BET characterizations reveal the nanocomposites had a larger specific surface area and pore volume in comparison to the individual CoFe₂O₄. The composite was employed to evaluate the adsorption and peroxymonosulfate (PMS)-activated ability of 4-NP and 2,4-DCP elimination. The adsorption equilibrium could be achieved within 60 min, following the pseudo-second-order kinetic model and the Langmuir isotherm model. The nanocomposites (0.2 g·L⁻¹) achieved exceeding 96 % decomposition efficiencies toward 4-NP and 2,4-DCP (0.1 g·L⁻¹) after 15 min by PMS (5.29 mM) activation. Notably, the reaction system displayed effective catalytic performance across pH 5 − 11 and resistance to the existence of saline ions and humic acid. According to the free radical quenching experiments and electron paramagnetic resonance, the non-radical route dominant by ¹O₂ and few HO^• and SO₄^•− were affirmed to participate the reaction. The recyclable MIL-101/CFO/PMS system approached high adsorption and catalysis ability for phenolics remediation in the environmental application.