Nearly zero peroxydisulfate consumption for persistent aqueous organic pollutants degradation via nonradical processes supported by in-situ sulfate radical regeneration in defective MIL-88B(Fe).

The porous defective MIL-88B(Fe) with abundant oxygen vacancies and Fe-N sites was fabricated to accomplish nearly zero peroxydisulfate (PDS) consumption for persistent bisphenol A (BPA) degradation via electron-transfer pathway (ETP). Interestingly, the generated sulfates during ETP were oxidized to yield the confined sulfate radicals and to accomplish the peroxydisulfate regeneration in the fine-tuned MIL-88B(Fe), which was verified by series experiments and DFT calculations. Further studies suggested that the optimal De-MIL-88B(Fe)-1.25 catalyst achieved the persistent nonradical reactions for BPA decomposition under visible light irradiation with both low input and low consumption of PDS. It was the first case to achieve nearly zero PDS consumption for emerging pollutants elimination, which provided new strategy to design and tune defective metal-organic frameworks for the purpose of reducing the stoichiometry between PDS and contaminants for nearly zero PDS consumption. [Display omitted] • The defective MIL-88B(Fe) with rich oxygen vacancies and Fe-N sites was fabricated. • The structure was affirmed by various techniques like XAS and DFT calculations. • The relationships between structure and catalytic activity were confirmed by QSARs. • De-MIL-88B(Fe)-1.25 achieved persistent ETP by PDS regeneration for BPA removal. • The PDS regeneration mechanism was verified by experiments and DFT calculations. [ABSTRACT FROM AUTHOR]