Self-Regenerating PFOA Defluorination in Groundwater via Endogenous Electron Feedback in Biomimetic Molecular Trap

The high dissociation energy of C-F bonds and the energy-limited low-temperature groundwater environment jointly render PFOA defluorination kinetically inaccessible, while sluggish regeneration of metal active centers constrains catalytic turnover in advanced oxidation systems. Here, we report a biomimetic molecular trap, hexadecafluorinated cobalt phthalocyanine (F₁₆CoPc), inversely designed from the pollutant template, that enables PFOA defluorination at environmentally relevant temperatures by constructing a preorganized reaction interface and triggering a substrate-driven intrinsic regeneration cycle. The electron-deficient perfluorinated π-plane of F₁₆CoPc recognizes PFOA mainly through anion-π interactions, assisted by fluorine-fluorine interactions, thereby forming a preorganized interfacial configuration. This configuration lowers the activation enthalpy and confines reactive species to surface-bound radical states, preventing nonproductive diffusion and loss into the bulk phase. Crucially, degradation-derived perfluoroalkyl radicals (C_nF_2n+1^•) remain in molecular-scale proximity to Co centers, where they reduce Co³⁺ generated during PMS activation back to active Co²⁺ via short-range electron transfer, regenerating catalytic turnover. By inheriting key structural recognition motifs, partially defluorinated intermediates further maintain an iterative recognition-degradation-regeneration cycle. F₁₆CoPc achieved >80% defluorination at 30 °C and >30% at 10 °C, highlighting the potential of molecular template engineering as a biomimetic strategy for groundwater remediation and for overcoming C-F activation and metal-center deactivation.