Enhancing visible-light-driven photocatalysis: unveiling the remarkable potential of H₂O₂-assisted MOF/COF hybrid material for organic pollutant degradation

In this study, we synthesized MOF/COF hybrid material (NH₂-MOF-5/MCOF) by integrating NH₂-MOF-5 (Zn) with a melamine-based COF (MCOF) to target the photocatalytic degradation of methylene blue (MB) dye. Characterization using SEM, XRD, XPS, FT-IR, and UV-DRS confirmed the synthesized MOF/COF hybrid's exceptional photocatalytic performance under visible light. The addition of H₂O₂ significantly enhanced the photocatalytic degradation, achieving removal rates of 90%, 92%, and 57% for 11.75 mg L^-1, 30 mg L^-1, and 83 mg L^-1 of MB, respectively. Kinetic studies revealed first-order kinetics, with a rate constant nearly 3.5 times higher with added H₂O₂. We proposed a comprehensive photocatalytic mechanism elucidated through energy band structure analysis and scavenger tests. Our findings revealed the formation of a heterojunction between NH₂-MOF-5 and MCOF, which mitigates electron-hole recombination, with ∙OH identified as the principal species governing methylene blue degradation. Moreover, the NH₂-MOF-5/MCOF hybrid displayed excellent reusability and chemical stability over six cycles. Notably, this H₂O₂-assisted hybrid material demonstrated the removal of 99% of ibuprofen, a pharmaceutical drug, showcasing its broad applicability in removing organic contaminants in aqueous solutions, thereby holding great promise for wastewater treatment.