CeO2 decorated ZnO nanoparticles: Enhanced photocatalytic and antimicrobial properties for sustainable industrial and biomedical applications

CeO 2 -decorated ZnO nanomaterials with different CeO 2 contents (1.81-13 wt% CeO₂) were synthesized via a cost-effective co-precipitation method to develop multifunctional materials for environmental and biomedical applications. Physicochemical characterization confirmed the formation of ZnO-CeO 2 heterojunctions, with the ZnO-2.87CeO 2 sample exhibiting significant lattice expansion as well as a high concentration of interfacial ions and oxygen vacancies as confirmed by XPS. This optimal composition demonstrated high photocatalytic activity, achieving 99.4% degradation of methylene blue (MB) under direct sunlight and 92.5% under solar simulator exposure within 1 h. Furthermore, the nanocomposites showed enhanced antifungal activity against A. niger (MIC: 49.1 mg/L) and increased antibacterial efficacy against four pathogenic strains ( E. coli, P. aeruginosa, K. pneumoniae, E. cloacae ) under light activation (MBC: 0.7-11.3 mg/L), driven by photocatalytically generated reactive oxygen species (ROS). These results highlight the potential of ZnO-CeO₂ heterojunctions as high-performance agents for wastewater treatment and antimicrobial coatings.