Asymmetric chemical bond modified CuO in-situ grown on copper foam cooperates with pollutants to promote copper valence cycling in peroxymonosulfate activation

A Cu-O-Bi bond-engineered CuO catalyst (FB-CuO) was constructed on copper foam via in-situ growth to break the symmetry of the CuO coordination environment and accelerate Cu redox cycling during peroxymonosulfate (PMS) activation. Its activation mechanism was systematically investigated through quenching experiments, electron paramagnetic resonance (EPR), metal-site poisoning tests, electrochemical analysis, spectral characterization, and density functional theory (DFT) calculations. FB-CuO achieves 93.32% atrazine (ATZ) degradation within 60 min, exhibits excellent reusability over six cycles, maintains over 65% removal efficiency in tap water and lake water, enables 12 h continuous rhodamine B removal in a flow-through reactor, and shows good selectivity toward other nitrogen-containing organic pollutants. Mechanistic results demonstrate that Cu-O-Bi sites optimize the microenvironment of Cu centers, enhance PMS adsorption, and accelerate the Cu(II)/ Cu(III) redox cycle for radical generation, while ATZ coordinates with surface Cu sites through Cu-N bond formation, promoting Cu(II) reduction to Cu(I) and further accelerating PMS activation and Cu redox cycling. These findings establish a mechanistic framework for coupling active-site engineering with catalyst-pollutant interaction to intensify PMS activation, and provide a general design principle for robust structured catalysts in persulfate-driven environmental catalysis.