Laser-Anchored Ru Single-Atoms Enable Paired PET Plastic and Nitrate Upcycling into Formate and Ammonia

초록

Electrochemical upcycling of nitrate (NO3-) and polyethylene terephthalate (PET) waste into value-added chemicals offers a promising strategy for simultaneous pollution mitigation and resource recovery. However, progress in this field is hindered by the limited availability of high-performance electrocatalysts. Herein, we report a rapid CO2 laser irradiation strategy for synthesizing Ru single-atom (RuSA) catalysts anchored on L-tryptophan (Trp) nanodomain-assembled Co3O4 nanocubes (RuSA/Trp-Co3O4) within 3 min, enabling high active-site exposure and utilization efficiency for both the electrocatalytic nitrate reduction reaction (NO3RR) and the ethylene glycol oxidation reaction (EGOR), where ethylene glycol (EG) is a key PET-derived monomer. The electron-rich Ru-N and Ru-O coordination environments, together with strong metal-support interactions, modulate the electronic structure, inducing a downward shift of the d-band center that optimizes the adsorption of key intermediates (*CH2OHCOOH and *NO). As a result, RuSA/Trp-Co3O4 delivers high Faradaic efficiencies of 94.21% for selective C-C cleavage toward formate synthesis via the EGOR at 1.40 V vs RHE and 88.28% for NH3 formation via the NO3RR at -0.20 V vs RHE. In situ spectroelectrochemistry and theoretical calculations reveal that the synergistic effects of isolated Ru sites suppress EG overoxidation and NO3- overreduction, thereby enabling efficient hybrid electrolysis for the concurrent upcycling of NO3- and PET hydrolysate into NH3 and formate, respectively, while simultaneously facilitating the recovery of high-purity terephthalic acid. This work establishes a scalable design strategy for high-utilization single-atom catalysts for coupled waste upcycling reactions.

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