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

ABSTRACT

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.