Localized Dipole Construction and Electron Configuration Modulation Driven by Cerium Doping Enables Effective Decontamination and Resource Recovery of Chlorophenols

The modulation of electronic configuration in metal-based catalysts is a critical strategy to achieve effective decontamination and resource recovery of chlorophenols as polymers. Herein, the electron density and spin state of carbon-encapsulated nanoscale zerovalent-iron was modulated via doping cerium (Ce lat -C@Fe 0 ), which enabled efficient periodate (PI) activation and triggered the polymerization of 2,6-dichlorophenol (2,6-DCP) via concerted electron–proton transfer (CEPT). The incorporation of Ce, which was larger in atomic size than Fe, caused tensile strain within the Fe 0 lattice, which consequently enhanced electron accumulation at Fe centers via localized dipoles and stabilized unpaired electrons in a low-occupancy state. This electron structural evolution facilitated the catalytic mechanism transition from hydroxyl radical (HO • ) attack to an interfacial electron-transfer process. Mechanistic investigations showed that interfacial electron transfer coupled with proton transfer (CEPT) initiated the formation of phenoxy radicals (PhO • ), which mediated the molecular C–O polymerization of 2,6-DCP, rather than conventional mineralization. Consequently, the Ce lat -C@Fe 0 /PI system exhibited sustainable wastewater purification capacity ( k -value = 10.04 min –1 ·M –1 ), surpassing most reported catalysts in PI-based catalytic territory. This study offers a novel adaptive paradigm for expanding the potential application of polymerization technology via inducing tensile strain to regulate electron configuration.