Selective electro-reforming of waste polyethylene terephthalate-derived ethylene glycol into C2 chemicals with long-term stability

Abstract

Electro-oxidation of ethylene glycol (EG) derived from polyethylene terephthalate (PET) into value-added C₂ products is essential for the electro-reforming of waste PET. However, achieving high selectivity and stability in the EG oxidation reaction (EGOR) remains a significant challenge. Herein, we successfully fabricated segregation-less Pd₁Ag₁ alloy nanoparticles (NPs) that can be used for the electro-reforming of waste PET into glycolate C₂ products with high selectivity (97%) and long-term stability (>500 h). Electrochemical measurements and in situ Fourier-transform infrared spectroscopy (FTIR) results reveal that the addition of Ag atoms improves glycolate selectivity by reducing its adsorption on Pd active sites. In addition, the surface *OH species generated on Ag sites facilitate the rapid oxidation of toxic carbonyl species, thereby improving the stability of Pd sites. Therefore, the synergistic effects of Pd₁Ag₁ NPs provide an effective way for practical electro-reforming of real-world waste PET into value-added products with high selectivity and stability.