Self-Assembly of Nanosheet Supported Fe-MOFs Heterocrystal as Reusable Catalyst for Boosting Advanced Oxidation Performance via Radical and Nonradical Pathways

Heterojunction catalysts have drawn mounting interest for the visible light-driven Fenton reaction, and bring tremendous opportunities for environmental remediation. Herein, a BiOI/MIL-53(Fe) Z-scheme heterojunction (named BMFe) was synthesized for the first time via a facile strategy. Compared with pristine BiOI and MIL-53(Fe) catalysts, the 2D/3D heterojunction catalyst manifested remarkable catalytic performance toward degradation of phenol, bisphenol A, methylene blue and carbamazepine, which is attributed mainly to the interfacial integration and efficient charge separation. By virtue of coupling at the interface, as confirmed by XPS, 57Fe Mössbauer spectroscopy and DFT calculations, the BMFe catalyst promoted the transfer of electron-hole pairs via Z-scheme and improved the chemical activation of hydrogen peroxide. The subsequent holes, free radicals and nonradical can effectively and continuously decompose pollutants, achieving a positive synergistic effect between photocatalysis and Fenton reactions. Simultaneously, the specially designed BiOX(X=Br, Cl)/MIL-53(Fe) and BiOI/Fe-MOFs(MIL-101, MIL-88) heterojunctions also exhibited advanced oxidative capacity for organic pollutants. Given their practical value for industrial applications, BMFe-beads (1.0 ± 0.15 mm) synthesized via a blend crosslinking method can significantly advance long-term stability and recyclability. The integration of Fe-based metal organic frameworks with bismuth oxyhalide semiconductors provides a new perspective on developing heterojunction catalyst for environmental remediation.