Electrocatalytic upcycling of polyethylene terephthalate plastic to co-generated hydrogen and formate via a bifunctional Ni4Mo/Fe3O4 heterointerface

The introduction of a dual-reaction coupling mechanism that simultaneously integrates ethylene glycol oxidation reaction (EGOR) and hydrogen evolution reaction (HER) on two electrodes to selectively produce the target product is of great importance. By precisely controlling the composition and electronic structure of the catalyst, this study produced catalytic materials with specific morphologies, achieving long-term stability; furthermore, by integrating a water electrolysis strategy, the research simultaneously achieved low energy consumption and high Faradaic efficiency. The Ni 4 Mo/Fe 3 O 4 catalyst achieves outstanding EGOR activity with a current density of 50 mA cm −2 at 1.42 V vs . RHE and a Faraday efficiency of 97% for formate production. For HER, it exhibits a low overpotential of 60 mV at 10 mA cm −2 and a Tafel slope of 67.46 mV dec −1 , surpassing most non-precious metal catalysts. Drawing on theoretical calculations, it is the electron coupling at the heterointerface and synergistic interactions between Ni and Mo sites that optimize the reaction pathway and lower the reaction energy barrier, thereby explaining the superior performance of Ni 4 Mo/Fe 3 O 4 . The work establishes interfacial engineering as a viable strategy for developing advanced bifunctional electrocatalysts, thereby addressing PET waste management and clean energy production sustainably.