Modulating Adsorption Behavior by Single-site Pt on RuO2 for Efficient Electrosynthesis of Glycolic Acid from Plastic Wastes

Abstract

Electrochemical upcycling of polyethylene terephthalate (PET) wastes into valuable glycolic acid (GA) is an ideal solution for resource utilization. However, simultaneously achieving high activity and selectivity remains challenging due to the over-oxidation and C-C cleavage during ethylene glycol (EG) oxidation in PET hydrolysate. Herein, we develop an atomically isolated Pt on RuO2 (Pt1/RuO2) catalyst composed of high-density Pt-Ru interfaces that ensure single-site adsorption of EG, enrich surface *OH coverage and weaken *CO−CH2OH intermediate adsorption, thereby synergistically promoting GA generation. Specifically, Pt1/RuO2 delivers a remarkable mass activity of 8.09 A/mgPt, as well as a high GA Faradaic efficiency (95.3%) and selectivity (96.9%). Under membrane electrode assembly conditions, Pt1/RuO2 realizes a stable electrolysis over 500 h at 6 A with a GA yield rate of 4.06 g h-1. In-depth theoretical and in situ spectroscopic investigations reveal the synergy between isolated Pt and oxophilic RuO2 plays a crucial role in high-efficiency EG-to-GA conversion. This study offers valuable insights for the rational design of advanced catalysts for GA synthesis from PET wastes via a single-site doped bimetallic strategy.