Synergistic OH ⁻ /H ₂ O Engineering and Dynamic Potential Modulation for Efficient Upcycling of PET Waste to Glycolic Acid Using H ₂ O as the Oxygen Source

Abstract

ABSTRACT The conversion of polyethylene terephthalate (PET)‐derived ethylene glycol (EG) into value‐added glycolic acid (GA) by electrocatalysis using H 2 O as an oxygen source is a promising pathway for the sustainable valorization of plastic waste. However, the commonly used Pt and Pd catalysts suffer from undesirable activity and fast deactivation. Herein, we designed a AuPtPdRh medium‐entropy aerogel (MEA) with multi‐site synergies, coupled with dynamic potential modulation strategy, to achieve efficient GA synthesis. The AuPtPdRh MEA reduces the overall energy barrier through a potential relay‐type catalytic mechanism across distinct active sites. The potential sweep‐step hybrid electrolysis (PS‐SHE) modulation strategy establishes a “progressive pre‐enrichment—pulsed cleaning‐regeneration” cycle, which enhances catalytic activity and stability. This system achieves 98% Faradaic efficiency (FE) for GA (FE GA ), as well as an GA production rate (PR GA ) of up to 8.82 mmol cm −2 h −1 . Additionally, it can maintain stable operation for 500 h at an ampere‐level current density (0.25 A cm −2 ) in a membrane‐free flow cell. The universality of this approach is further demonstrated for methanol, ethanol, and propanol electrooxidation, providing a versatile platform for biomass valorization.