Efficient Concentration and Complete Destruction of Short-Chain and Emerging PFAS in Contaminated Water via...

Short-chain and emerging per- and polyfluoroalkyl substances (PFAS) pose a significant threat to water security due to their high mobility and environmental persistence. Current strategies relying solely on adsorption or degradation remain inefficient and incomplete solutions. Herein, a closed-loop "Concentrate-&-Destroy" strategy integrating an interface engineering-enhanced sorbent of the polypyrrole (PPy) nanostructured coating carbon felt (PPy@P-CF) with Cu²⁺-mediated photochemical destruction is presented. This designed PPy@P-CF enabled rapid and efficient adsorption of short-chain PFAS (C2-C4) and emerging GenX, with equilibrium achieved within 300 s and maximum sorption capacities reaching 283.2-572.1 mg g^-1, surpassing those of granular activated carbon (GAC) and CF by over 21 and 5 times, respectively, under identical conditions. Dynamic column tests demonstrated a 5-fold improvement in breakthrough volume (exceeding 4000 bed volumes) compared to GAC and CF columns. Furthermore, the spent PPy@P-CF can be regenerated by solvent washing for reusability, and Cu²⁺-mediated photochemical degradation achieved complete defluorination of concentrated PFAS in eluate within 5 h by a ligand-to-metal charge transfer process. In practical applications, a bulk PPy@P-CF module achieved > 96% removal of 27 diverse PFAS from real contaminated water, followed by complete photochemical defluorination. This integrated approach provides an adoptable solution for eliminating persistent short-chain and emerging PFAS.