Laser‐Stabilized Atomically Dispersed Ru on Co ₃ O ₄ Nanosheets for C ₁ /C ₂ Selectivity in PET Electro‐Upcycling

ABSTRACT Herein, we present a rapid and one‐step CO ₂ laser irradiation strategy that stabilizes Ru single atoms (RuSAs) on two‐dimensional Co ₃ O ₄ nanosheets (RuSA/Co ₃ O ₄ ) within 3 min under ambient conditions. The Co ₃ O ₄ substrate was derived from microwave‐synthesized α‐Co(OH) ₂ (2.45 GHz, 1 min) followed by thermal oxidation at 350°C for 1 h, affording a spinel oxide with ordered Co ²⁺ /Co ³⁺ sites. Distinct from carbon‐supported single‐atom catalysts (SACs) systems, the oxide support functions as both an anchoring matrix and active redox component during the ethylene glycol oxidation reaction (EGOR). Combined experimental and theoretical analyses reveal that α‐Co(OH) ₂ promotes C ₂ ‐selective C─H bond oxidation to glycolate, Co ₃ O ₄ favors C─C bond cleavage toward C ₁ products (formate), and RuSA/Co ₃ O ₄ enables tunable and balanced C ₁ /C ₂ product formation during the EGOR, highlighting the role of RuSA sites in regulating EGOR pathways with excellent stability over 100 h. Beyond the EGOR, practical polyethylene terephthalate (PET) waste upcycling was demonstrated using PET hydrolysate feedstock; the RuSA/Co ₃ O ₄ catalyst achieves high recovery yields of terephthalic acid (88.0%), formate as potassium diformate (90.6%), and glycolate as potassium glycolate glycolic acid (91.3%). This study elucidates laser‐induced defect–SA interactions for rapid SAC fabrication and establishes an integrated platform coupling SA engineering with plastic waste upcycling.