Magnetic COF/MOF hybrid: An efficient Z-scheme photocatalyst for the visible light-assisted degradation of tetracycline and malachite green

Herein, COF (Covalent Organic Framework), MIL100 (Materials Institute Lavoisier), CuFe2O4 and COF/MIL100/CuFe2O4 hybrids were synthesized and characterized. The COF/MIL100/CuFe2O4 hybrids with different amounts of COF (0.3, 0.6, and 0.15 g) were competently synthesized through a hierarchical approach and denoted as COF/MIL100/CuFe2O4 (2:1), COF/MIL100/CuFe2O4 hybrid (1:1), and COF/MIL100/CuFe2O4 hybrid (1:2), respectively. This hybrid exhibited impressive photocatalytic capabilities for the degradation of pharmaceutical (TCN: tetracycline) and dye (MG: Malachite Green) contaminants. The MG degradation (100 mL of 20 mg/L dye solution at natural pH) using COF, MIL100, CuFe2O4, hybrid (1:1), hybrid (2:1), and hybrid (1:2) was 66 %, 43 %, 32 %, 99 %, 95 %, and 85 %, respectively. Also, the TCN removal (100 mL of solution and 5 mg of composites at natural pH) was 59 %, 61 %, 34 %, 80 %, 77 %, and 74 % using COF, MIL100, CuFe2O4, hybrid (1:1), hybrid (2:1), and hybrid (1:2), respectively. Examination of degradation kinetics demonstrated first-order behavior for tetracycline and zero-order behavior for malachite green. Active species assessment, emphasizes the substantial involvement of holes (h+), and hydroxyl ( OH) radicals in the photodegradation mechanism. Also, the hybrid provided good stability and performance even after being used for five cycles. This research presents a concept for the development of an efficient photocatalyst, leveraging the enhanced performance and magnetic separation capacity achieved through the synergistic combination of MIL100, COF, and magnetic nanoparticles (CuFe2O4).