The Answer Lies within the Puzzle Piece: PET-Derived Defect-rich MOFs Boosting Ethylene Glycol Oxidation for Total-Product PET Upcycling

Chemical recycling of poly(ethylene terephthalate) (PET) is limited by harsh depolymerization conditions and the low-value utilization of terephthalic acid (TPA) and ethylene glycol (EG). Herein, we report a “one-stone-three-birds” strategy that couples PET depolymerization, TPA utilization, and EG upgrading for total-product upcycling. Waste PET serves as an in situ slow-release terephthalate precursor, whose gradual, incomplete hydrolysis dynamically perturbs metal–ligand stoichiometry, generating missing-linker defects and oxygen-deficient, coordinatively unsaturated environments in a bimetallic MOF (NiCo-PET). Relative to NiCo-MOF prepared from commercial TPA, NiCo-PET exhibits 67% higher spin concentration and enhanced EG oxidation, requiring only 1.29 V vs RHE at 50 mA cm–2 while achieving 93.6% formate Faradaic efficiency and stable operation for 24 h at 2 A cm–2. Operando analysis confirms favorable reconstruction into high-valence oxyhydroxides. This work valorizes both PET-derived products without additional purification or isolation, offering a sustainable route to total-product plastic upcycling.