MOF-808-Based Nanocomposites as Defect-Chemically Bonded Z-Scheme Heterojunctions for Photocatalytic Hydrogen Evolution and Antibiotic Degradation

Developing MOF nanomaterials with optimal charge transfer pathways is crucial for achieving long-term and stable photocatalysis. However, the wide bandgap and excited-state spatiotemporal transformation characteristics of MOFs significantly limit their practical applications. In this study, a chemically bonded Z-scheme heterojunction was constructed by coupling surface-defective MoS2 with MOF-808, and the formation of the Zr–O–S chemical bond was comprehensively analyzed using XAFS, in situ infrared spectroscopy, and theoretical calculations. The results demonstrate that the bimetallic catalytic system, linked by chemical bonds, promotes rapid transfer of photogenerated carriers and significantly enhances the robust redox capability of the MOF-808 nanomaterial. The 2-MoS2/MOF-808 composite achieved a quantum yield of 65.5% and exhibited higher electron consumption rates during photocatalytic hydrogen evolution, demonstrating a clear advantage over similar catalysts. Moreover, 2-MoS2/MOF-808 also demonstrated efficient degradation of antibiotic-containing wastewater. Additionally, a bismuth-based MOF-808 heterostructure was synthesized using the same strategy, confirming the general applicability of defect-chemical bond engineering. This work not only provides a perspective for heterojunction photocatalysis but also makes a significant breakthrough in the application of nanomaterials.