Phosphorus-doped Co/Fe bimetallic catalyst for efficient peroxymonosulfate activation toward phenol degradation

Utilizing bimetallic synergy presents a promising approach for creating exceptionally effective catalysts for peroxymonosulfate (PMS) activation. In this study, a Co Fe bimetallic catalyst (Co8Fe1-P1-NC) was constructed by regulating the Co/Fe doping ratio and further introducing phosphorus doping. During PMS activation for phenol (Ph) degradation, Co8Fe1-P1-NC exhibited outstanding catalytic performance. Under the optimized conditions, the Co8Fe1-P1-NC/PMS system achieved complete removal of Ph within 2.5 min, with an apparent rate constant as high as 2.058 min −1 and a total organic carbon (TOC) removal efficiency of up to 80%. Combined results from quenching experiments, electron paramagnetic resonance (EPR), in situ Raman spectroscopy, electrochemical measurements, and premixing tests demonstrated that O 2 •− , 1 O 2 , high-valent metal species, and electron-transfer pathways collectively contributed to Ph degradation. Theoretical calculations indicate that Fe and P doping make the PMS adsorption energy more negative and elongate the O O bond (l O–O ), thereby facilitating PMS activation on the catalyst. Co8Fe1-P1-NC also showed excellent broad-spectrum degradation capability toward various phenolic pollutants, achieving complete removal within 3 min. These findings indicate that the combined regulation of metal active sites and electronic structure through bimetallic synergy and nonmetal doping can significantly enhance PMS activation efficiency, providing a new avenue for the design of high-performance catalysts.