Construction of antimicrobial CeO2/Fe2O3 nanomaterials with enzyme-like activity and study of their mechanisms

This study employed rare earth element, Ce, and elemental Fe to prepare antimicrobial nanocomposites with enzyme-like activity. The materials were characterized by SEM, EDS, and XRD, as well as antimicrobial and drug resistance properties were tested. XPS analysis revealed a change in the valence state of Ce 3d in CeO 2 /Fe 2 O 3 on addition of Fe. Furthermore, UV -vis spectral results showed that the band gap of the composite material decreased after composite formation. The creation of a heterogeneous structure was a significant factor responsible for enhancing the antimicrobial performance. The study analyzed the peroxidase (POD) activity of the materials using UV -vis spectroscopy. Results showed that the enzyme activity of the composites was significantly enhanced, compared to the individual materials. This enhancement combined with H 2 O 2 to induce the production of ROS, resulted in a significant increase in the antimicrobial effect. The antimicrobial rate of the composite material exceeded 90 % at 250 mu g/mL concentration. The antibacterial mechanism revealed that it primarily operated through synergistic effects of ROS, ionic dissolution, and damage by adsorption. It also had an apparent inhibitory effect on bacterial micro-organisms in water, which has wider application prospects.