Synthesis of novel Bi_0.5Na_0.5Ti_0.95 (Ni_0.2Fe_0.2Sb_0.6)_0.05O₃ perovskite material used as a photocatalyst for methylene blue degradation under sunlight irradiation

In this study, we synthesized a novel ceramic material Bi_0.5Na_0.5Ti_0.95 (Ni_0.2Fe_0.2Sb_0.6)_0.05O₃ named BNT-NFS via the solid-state route and assessed its efficacy as a photocatalyst for removing methylene blue dye from wastewater. The synthesized samples underwent thorough characterization using thermogravimetric analysis combined differential thermal analysis TGA-TDA, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, and UV–Visible measurements. TGA-DTA and XRD analyses confirmed the successful formation of BNT-NFS material at 1150 °C, exhibiting a hexagonal phase structure. FTIR analysis revealed an intense band at 421 cm⁻¹, corresponding to metal-oxide vibrations in the BNT-NFS spectrum. SEM observations unveiled a distinct microstructure of BNT-NFS composed of grains of varying sizes. BET analysis indicated that the prepared BNT-NFS powder possessed a significant specific surface area of 261.36 m²/g. Optical and photocatalytic assessments demonstrated that BNF-NFS perovskite is a semiconductor material with a band gap of 2.73 eV, exhibiting satisfactory photocatalytic activity for methylene blue MB dye removal. Notably, the removal efficiency reached 60% after 210 min of exposure to sunlight irradiation. This result is better than that registered for the pristine BNT.