The utilization efficiencies of peroxide and the evolved reactive species are typically low in advanced oxidation processes due to their self-quenching or scavenging by background factors in water matrices. Here, we design a new Co-based metal-organic framework (PKU-24) with a six-coordinate structure that induces strong electron localization and suppresses the redox activity of Co sites, thereby blocking the electron-transfer pathway. Interestingly, electron-rich pollutants with oriented dipole moments can act as molecular "switches", effectively turning on PKU-24 activity for peroxymonosulfate (PMS) activation. Computations reveal that the dipole moment of pollutants is the decisive descriptor governing the behavior of organic contaminants in activating inert Co centers and reopening the electron-transfer channel to mediate SO5 •- toward selective singlet oxygen generation. Additionally, this work develops a large-scale synthesis method for PKU-24 with a single synthesis yield of ∼0.55 kg (costing ∼0.52 USD g-1) and achieves long-term, efficient, continuous treatment of organic wastewater. This work introduces a new principle for the design of pollutant-sensitive Fenton-like catalysts to achieve effective organic elimination while significantly reducing peroxide consumption.
Li et al. (Sun,) studied this question.