Synthesis and Physicochemical Characterization of Magnetic Core-Shell Nanoparticles as Potential Photocatalysts for Caffeine Degradation

The study addresses the growing presence of emerging contaminants in aquatic environments, particularly caffeine, which is widely detected and linked to human activity. The objective was to synthesize and characterize core-shell magnetic nanoparticles composed of magnetite (Fe₃O₄) coated with semiconducting oxides (TiO₂, ZnO, and Nb₂O₅) for potential future application in the photodegradation of caffeine. The nanoparticles were produced in stages and characterized using techniques such as FTIR, XRD, point of zero charge determination, and adsorption tests. The results confirmed the formation of the expected structures and the preservation of the magnetite's crystallinity following the coating process. Although the adsorption tests did not show significant caffeine removal, the materials exhibited properties suitable for application in photocatalytic processes under UV radiation, including potential for reuse and magnetic separation.