Abstract

Electro-reforming of polyethylene terephthalate (PET) via selective C–H and C–C bond cleavage of its monomer ethylene glycol (EG) offers a promising strategy for plastic upcycling into high-value C2 and C1 products. However, achieving sustainable catalytic control over product selectivity remains a critical challenge. Herein, we report the carbon monoxide-mediated synthesis of palladium nanosheets (PdNS) as the first palladene substrate for atomically dispersed dimer catalysts. We further introduced the first report of NiMo dimer immobilization on PdNS (NiMo-DA/PdNS) using a rapid CO₂ laser irradiation (~10.6 µm, ~7 W) in 10 min, where localized heating drives Ni²⁺ and Mo⁶⁺ reduction, Ni anchoring on Pd sites, and Mo migration–Ni coupling to form stable heteronuclear Ni–Mo dimers via strong d-orbital hybridization and thermodynamic preference, overcoming the limitations of conventional atomic-level catalyst syntheses. The NiMo-DA/PdNS platform exhibits enhanced EG oxidation reaction (EGOR) activity with potential-dependent product selectivity. At 1.0 V vs. RHE, glycolate (C2 product from selective C–H bond cleavage) was obtained with a Faradaic efficiency (FE) of 81% and a yield rate (YR) of 1.14 mmol h^‒1 cm^‒2. At 1.6 V vs. RHE, formate (C1 product from C-C bond cleavage) was selectively produced with an FE of 77.9% and a YR of 0.39 mmol h^‒1 cm^‒2. Density functional theory (DFT) calculations further corroborate these performance trends and elucidate the mechanism that C–C scission in EG is accompanied by electron transfer to the catalyst surface, which lowers the reaction free energy at higher potentials, thereby enhancing C1 production, most prominently on NiMo-DA/PdNS. This work enables the first demonstration of concurrent high selectivity toward both glycolate and formate while efficiently recovering high-purity terephthalic acid monomers from PET hydrolysate electrolysis over 50 h. Techno-economic analysis (TEA) confirms the economic viability with net profits of USD 1,785.08 tPET^‒1 (glycolic acid + TPA) and USD 1,168.25 tPET^‒1 (formic acid + TPA), highlighting the practical potential of integrating advanced atomically engineered catalysts with real-world PET upcycling.