Oxygen-vacancy-mediated silver release from mesoporous CeO₂ for durable antimicrobial coatings

Silver ions (Ag⁺) have been widely used in the prevention and control of bacterial infections due to their excellent broad-spectrum antimicrobial properties. However, Ag⁺ tends to undergo rapid release in complex physiological environments, which limits its long-term application. To address these challenges, this study developed a novel Ag-loaded porous ceria (CeO₂) composite. The abundant oxygen vacancies and porous structure of CeO₂ not only provide a uniform loading platform for silver nanoparticles, but also effectively promote the conversion of Ag⁰ to Ag⁺. By establishing an in vitro release and antimicrobial kinetics evaluation system, the relationship between Ag⁺ release behavior and antimicrobial performance was systematically analyzed. Combined with the synergistic ROS generation mechanism of CeO₂/Ag, a complete synergistic antimicrobial pathway is constructed. The results demonstrated that mesoporous CeO₂ can regulate Ag⁺ release, achieving a favorable balance between antimicrobial efficacy and durability. Furthermore, the integration of the CeO₂/Ag composite into a powder coating system highlighted its potential for antimicrobial surface. This work provides a new strategy for designing functional materials with long-term and stable antimicrobial properties.