Selective Reductive Degradation of Tetracycline via Nitrogen-Doped Copper Nanowire Networks: Mechanistic Insights and Pathway Elucidation

The widespread contamination of aquatic ecosystems by the antibiotic tetracycline (TC) necessitates the development of advanced remediation technologies. Conventional advanced oxidation processes, while effective, often suffer from nonselectivity and the generation of toxic byproducts, leading to potential secondary pollution. This study introduces a novel nitrogen-doped copper nanowire (CuNW-N) network that enables the selective and reductive decontamination of TC through a precisely controlled electron-transfer mechanism. The CuNW-N network exhibits exceptional performance, achieving 98.2% TC removal with a 4-fold increase in reaction kinetics (0.034 min–1) compared to pristine CuNW (0.0084 min–1). Through a combination of advanced analytical techniques and theoretical calculations, we have identified a unique degradation mechanism involving sequential cleavage of electron-withdrawing groups based on their electrophilic strength hierarchy. This mechanism has been substantiated by systematic experimental evidence, including progressive intermediate m/z reduction and validated through density functional theory (DFT) calculations. The formation of Cu–TC surface complexes facilitates optimal pollutant adsorption, enabling pH-resilient removal efficiency while significantly enhancing system selectivity compared to conventional methods. This innovative approach not only addresses the limitations of nonselective degradation but also establishes a new paradigm for targeted antibiotic removal. Our findings provide fundamental insights into reductive degradation pathways and offer a promising foundation for developing advanced electrochemical systems for precise antibiotic removal in complex aqueous environments.