Synergistic OH <sup>−</sup> /H <sub>2</sub> O Engineering and Dynamic Potential Modulation for Efficient Upcycling of PET Waste to Glycolic Acid Using H <sub>2</sub> O as the Oxygen Source
Taoyuan Tian, Ya Zhou, Rui Shen, Yan Xu, Hongjie Yu, Hao Wang, Ziqiang Wang, Liang Wang, Kai Deng
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.