Facet-dependent haloperoxidase-like activities of CeO nanoparticles contribute to their excellent biofilm formation suppression abilities.

Biofilms adhering to different surfaces have significant negative impacts in various fields. Cerium oxide nanoparticles can serve as mimics of haloperoxidase for biological biofilm inhibition applications. The regulation of the exposed facet of CeO nanoparticles influences their efficiency in various catalytic processes. However, there is still a lack of systematic studies on the facet-dependent haloperoxidase-like activity of CeO. In the present study, the facet-dependent haloperoxidase activities and antibiofilm performance of CeO nanoparticles were elucidated through experiment analysis and density function theory calculation. The as-prepared CeO nanoparticles inhibited bacterial survival and catalyzed the oxidative bromination of quorum sensing signaling molecules, achieving biofilm inhibition performance. The antibacterial and biofilm formation suppression abilities were consistent with their haloperoxidase activities. The {111}- and {110}-facet CeO nanopolyhedra, as well as the {110}- and {100}-facet CeO nanorods, which had higher haloperoxidase activity showed better antibiofilm performance than the {100}-facet CeO cubes. The present findings provide a comprehensive understanding of the facet-dependent haloperoxidase-like activity of CeO. Furthermore, engineering CeO morphologies with different crystal facets may represent a novel method for significantly adjusting their haloperoxidase-like activity.