Preparation of NiCo hydroxide by chloride corrosion for electrocatalytic upcycling of polyethylene terephthalate plastic waste

Upcycling plastic waste into value-added chemicals is an innovative strategy that addresses environmental concerns and creates economic value. As one of the polyesters that is widely used, polyethylene terephthalate (PET) plastic waste is employed as the model substrate. Here we report a chloride corrosion method to synthesize bimetallic hydroxide catalysts on nickel foam. By using a nickel-cobalt hydroxide catalyst (NiCo-OH/NF), we demonstrate an electrocatalytic oxidation strategy to transform real-world polyethylene terephthalate (PET) water bottle into potassium formate and terephthalic acid (TPA) with high Faraday efficiency of 92.1 % at 1.40 V vs. RHE. The in situ spectroscopy and theoretical calculations provide insights into the catalytic mechanism especially active sites, pivotal intermediates, and favorable pathways. This work highlights the significant potential of electrochemical conversion as a means of achieving PET upcycling.