Anchoring Co–Fe alloy nano-grains on carbon fibers by an in situ alloying strategy to boost the catalytic performance for rapid oxidative degradation of emerging contaminants†

Advanced oxidation is regarded as the most promising pathway for the purification of hard-to-degrade contaminants. In this study, novel CoFe alloy-decorated carbon nanofibers (CoFe/CF) were constructed utilizing an alloy engineering strategy, which achieved the complete degradation of tetracycline with the rate constant reaching 97.92 × 10⁻³ min⁻¹. Integrated experimental analysis and density functional theory (DFT) simulations revealed that the synergistic integration of Fe and Co within the nanoalloy endowed the catalyst with an optimized electronic structure and distinct redox characteristics, markedly improving its capacity for peroxymonosulfate (PMS) activation. The low ecotoxicity and phytotoxicity of the intermediates during TC degradation confirmed the robust capability of CoFe/CF-800/PMS for the mineralization of TC-containing wastewater. Moreover, the pivotal role of CoFe nanoalloys for the generation of oxidative radicals was confirmed through an integrated experimental analysis, and a plausible mechanism for TC degradation was ultimately hypothesized. This work provides a case study about the electronic structure customization of bimetallic catalysts through alloy engineering and expands their applications for the elimination of hard-to-degrade pollutants.