Construction of Fenton-like systems based on hierarchical nanoconfinement for efficient antibiotic removal

Nanoconfinement is one of the effective strategies to improve the decontamination performance of nanomaterials in Fenton-like reactions. However, conventional nanoconfinement relying on nanotubular architectures suffers from segregated confinement of oxidants or pollutants, failing to establish directional interaction pathways between reactive species and target contaminants. To address this, we designed a hierarchical nanoconfinement strategy using Fe3O4/H2O2 system, enabling the simultaneous confinement of both oxidants and pollutants. First, a SiO2 layer was coated onto Fe3O4 and converted into a MnSiO3 shell, which selectively adsorbed tetracycline (TC), ensuring pollutant confinement. Next, the cavity size was precisely tuned by controlling the SiO2 interface thickness, spatially restricting H2O2 and enhancing bound & sdot;OH generation. This synergistic nanoconfinement mechanism improved the effective contact between active species and contaminants while eliminating active site competition. Compared to the Fe3O4/H2O2 system, the Fe3O4@MnSiO3/H2O2 catalyst exhibited a 1.7-fold increase in TC degradation rate and a 60 % enhancement in TOC removal efficiency. Moreover, it demonstrated robust performance in real aquaculture wastewater, sustained catalytic stability, and effective elimination of TC's antibacterial activity. This work not only advances nanoconfinement strategies but also offers a new paradigm for optimizing nanoconfined materials to enhance catalytic microenvironments.