Advanced photocatalytic degradation of textile dyes and removal of heavy metal ions from MFe₂O₄ using photo-Fenton mechanism

In this study, magnetic bimetallic spinel ferrites, MFe₂O₄ (M = Cu, Ni, Zn, and Cd) were synthesized by a feasible sol–gel self-combustion method. The single-phase cubic spinel structure and microstructural changes were confirmed by X-ray diffraction (XRD) analysis and field emission scanning electron microscopy (FESEM). The spinel structure’s functional groups (M–O bond) were verified through Fourier transform infrared (FTIR) spectroscopy. CuFe₂O₄ has the highest specific surface area (181.22 m²/g), which was determined by Brunauer-Emmett-Teller (BET) analysis. Magnetic study of the synthesized samples has been done by vibrating sample magnetometer (VSM) at ambient temperature. The catalytic activity of metal-ion-tailored MFe₂O₄ spinel ferrite nanoparticles was performed for the photo-Fenton degradation of cationic, anionic dyes, and removal of heavy metal ions [Cr(VI)] under visible light irradiation. The large specific surface area (181.22 m²/g), small value of the optical energy bandgap (1.55 eV), and better degradation efficiency of the photocatalyst are related to changes in shape, size, optimized magnetic, and optical properties. It acts as a promising material for the degradation of textile dyes and the removal of heavy metal ions from contaminated water.