Sustainable Synthesis and Characterization of Cerium Oxide Nanoparticles Using Camphora Leaf Extract for Efficient Dye Degradation

Cerium oxide nanoparticles were synthesized via a green method using Camphora leaf extract. Comprehensive characterization of the biosynthesized nanoparticles was conducted using XRD, UV-Vis, TEM, DLS, FT-IR, BET, PL and photocatalytic analyses. X-Ray diffraction confirmed the cubic crystalline structure of CeO2 with a crystallite size of 19±2 nm. UV-Vis spectroscopy showed a sharp absorption peak at 352 nm and minimum band gap of 3.52 eV, indicating strong photocatalytic potential. Both TEM and DLS analyses revealed that the majority of the particles were spherical, with an average size ranging from 20 to 21 nm, and moderate agglomeration. FT-IR analysis verified the involvement of phytochemicals in both the formation and stabilization of the biosynthesized nanoparticles. BET and BJH measurements demonstrated that the material possesses a high surface area and mesoporous structure, with an average pore diameter of 5 nm. PL spectra indicated that oxygen vacancies and other structural defects play a crucial role in enhancing charge carrier separation. Using sunlight as the irradiation source, the biosynthesized CeO2 nanoparticles achieved 91% degradation of methylene blue dye within 90 min. The catalyst demonstrated good stability across multiple reuse cycles, confirming their suitability for wastewater treatment applications. Overall, the experimental findings validate that this environmentally friendly synthesis approach can reliably produce highly active photocatalysts.