Activating peroxydisulfate with Co₃O₄/NiCo₂O₄ double-shelled nanocages to selectively degrade bisphenol A – A nonradical oxidation process

In this study, zeolitic imidazolate framework-67 (ZIF-67) derived Co₃O₄/NiCo₂O₄ double-shelled nanocages (DSNCs) were fabricated and utilized as catalysts to activate peroxydisulfate (PDS) for bisphenol A (BPA) degradation. The results showed that Co₃O₄/NiCo₂O₄ DSNCs exhibited superior BPA degradation performance over Co₃O₄ NCs and NiCo₂O₄ NCs. PDS combined with the interfaces of both the Co₃O₄ inner shell and NiCo₂O₄ outer shell to form complex, inducing the nonradical oxidation of BPA by electron abstraction. The double-shelled hollow structure helped to increase the instantaneous concentration of reactants in the void space of Co₃O₄/NiCo₂O₄ DSNCs, thus promoting the decomposition of BPA. The Co₃O₄/NiCo₂O₄ DSNCs had high selectivity for BPA degradation and were resistant to halogens and background organic matter in wastewater. Our work indicated that metal-organic framework (MOF)-derived nanomaterials with a hollow structure have a promising application prospect for persulfate-based advanced oxidation technology.