Unveiling the Optical and Dielectric Properties of MnFe2O4: A High-Performance Visible-Light Photocatalyst for Sustainable Rhodamine B Degradation

This study explores the optical and dielectric properties of MnFe2O4 nanoparticles synthesized via the co-precipitation method and their application in rhodamine B (RhB) photocatalytic degradation under visible light. Structural characterization confirmed the formation of a highly crystalline spinel ferrite with a coral-like porous morphology, enhancing the surface area for photocatalysis. X-ray photoelectron spectroscopy (XPS) analysis revealed Mn2+/Mn3+ and Fe2+/Fe3+ oxidation states, promoting charge transfer. Optical studies showed a narrow band gap (1.32 eV) and a valence band maximum at 1.07 eV, enabling efficient visible-light absorption. Dielectric analysis demonstrated strong polarization and minimal energy loss, facilitating charge retention. Photocatalytic experiments achieved 68.51% RhB degradation in 90 min, following pseudo-first-order kinetics (0.00932 min(-1)). Reusability tests confirmed 75% efficiency retention after six cycles. These results highlight MnFe2O4 as a promising, stable, and reusable photocatalyst for organic pollutant degradation and environmental remediation under visible light irradiation.