Theory‐Guided Single‐Atom Ru–N 4 Catalyst for Selective Catalytic Upcycling of Waste PET Plastic into Glycolic Acid

Converting waste polyethylene terephthalate (PET) plastic into glycolic acid (GA) is a revolutionary solution to alleviate energy shortages and plastic pollution. However, current catalytic methods are often limited by poor selectivity due to uncontrolled C─C bond cleavage. Here, through theoretical screening and experimental validation, we for the first time report a Ru–N 4 –C single‐atom catalyst, which achieves 100% co‐conversion of PET and ethylene glycol (EG), yielding high‐purity GA with 100% selectivity. Mechanistic investigations reveal that isolated Ru site selectively activate a single C─OH bond in EG, which subsequently facilitates the targeted coupling of the generated glycolaldehyde intermediate with hydroxyl groups adsorbed on adjacent C‐sites via a proximity effect. This pathway promotes the selective generation of GA from intermediate products HOCH 2 CO* and *OH, and inhibits GA peroxidation. The methodology demonstrates robust applicability to real‐world PET waste, PET‐containing mixed plastics, and other polyester plastics. Techno‐economic analysis and life‐cycle assessments further confirm the economic viability and environmental benefits of this process, establishing a sustainable technical route for upcycling of plastic waste.