Hollow carbon nanocages-loaded Co3O4 mediated electron transfer process for antibiotics removal via activated peroxymonosulfate: 1O2 dominated non-radical pathway

Addressing antibiotic water pollution through novel and effective strategies has become a critical endeavor. Increasing studies have shown that peroxymonosulfate (PMS) can be activated to generate singlet oxygen ( 1 O 2 ) by incorporating transition metals into carbon-based materials. Hollow carbon nanocages (HCNs) have proven to be a promising material for advancing energy conversion and battery technologies. However, studies based on HCNs in the field of Fenton-like reactions are scarce. In this study, the Fenton-like activity of HCNs-based catalysts were enhanced via confinement effect coupled with asymmetric Si coordination configuration. The hollow architecture endowed the catalyst with accelerated mass transport and markedly elevated utilization efficiency of active species. Co-HCNs delivered exceptional catalytic performance, accomplishing 99% tetracycline (TC) degradation within 40 min with a 67% mineralization rate, combined with robust anti-interference capacity in real-world water matrices. Density Functional theory (DFT) calculations indicated that the carbon-dense layer boosts the generation of 1 O 2 , in contrast to the cobalt core, which predominantly induced radical-mediated pathways. Integrated experimental analyses further confirmed that the degradation process is dominated by 1 O 2 , with other radicals playing synergistic contributions. Ecotoxicity evaluation verified the environmental compatibility of this process. This work further reveals an "oxidant-derived, dual-channel-driven 1 O 2 supply mechanism." This mechanism enhances the instantaneous supply capacity of 1 O 2 in the system and provides a clearer catalytic rationale for the selective oxidation of pollutants and stable purification in complex water matrices.