Ultrafast hypersaline wastewater decontamination via salinity-mediated surface redox with ultralow H₂O₂

The cost-effective maximum removal of organic contaminants in hypersaline wastewaters, which can promote wastewater reclamation and environmental protection, remains a pervasive global challenge. Current advanced oxidation processes based on hydroxyl radicals, are inefficient and energy intensive. Herein, we report a catalytic system comprising a Cu(I)/Cu(II)-coordinated N-modified graphene-like structure encapsulating Cu⁰ with cation-π interactions. Salinity-mediated ultrafast destruction of organic contaminants occurs via surface cleavage-hydrolysis circulation to mineralization with ultralow H₂O₂ assistance, facilitated by the strong electric field from salinity-contaminant-H₂O synergetic coordination. The catalyst exhibited high efficiency and stability, achieving a removal of ∼74.5 % of total organic carbon in hypersaline pesticide wastewater with 1.5 mM H₂O₂ consumption for 30 days. The degradation rate and H₂O₂ utilization increased by 18 to 194.1-fold, and 5 to 50-fold, respectively, for various hazardous organics and pharmaceutical wastewater with >100 mM salinity. Our findings highlight the potential utility of salinity driven surface redox for hypersaline wastewater treatment.