Improving the surface hydrophilicity of ZnFe-LDO for efficient catalytic ozonation achieves durable interfacial water purification

A ZnFe-LDH-derived ZnFe-LDO with high surface hydrophilicity was synthesized for catalytic ozonation to achieve durable water purification. It showed high catalytic performance towards ozone (O₃) decomposition to generate hydroxyl radicals (·OH), as well as enhancing the decontamination efficiency compared to ozonation alone. The ZnFe-LDO catalytic ozonation system promoted the degradation ratio of diatrizoic acid (DTA) from 20.6 % (ozonation alone) to 100 % within 10 mins, and the observed degradation rate constant (k_obs) of DTA under O₃/ZnFe-LDO system was 14.8 times that of O₃ alone system and 3.1 times that of O₃/ZnFe-LDH system. The constructed ZnFe-LDO and ZnFe-LDH catalyzed ozonation systems for water purification were comprehensively evaluated. ZnFe-LDO showed excellent structure and catalytic stability during the long-lasting catalytic ozonation process. The hydrophilic surface of ZnFe-LDO benefited the adsorption of H₂O, and O₃ was more readily adsorbed on the hydrated surface (E_ads = −1.89 eV) to react with -OH sites. The continuous flow technique based on the O₃/ZnFe-LDO process was well adopted for the purification of raw water. In short, regulating the surface hydrophilicity of ZnFe-LDO was an effective strategy to achieve durable catalytic ozonation.