Sol-gel synthesis of Tb-doped lithium-nickel ferrite anchored onto g-C3N4 sheets for efficient photocatalytic degradation of organic dyes

Due to the advancement of industrialization, water pollution has become an alarming global issue. Many organic dyes, such as crystal violet and rhodamine B, present in industrial wastewater are causing severe health problems. Both of these dyes are carcinogenic. For their degradation, ferrites are synthesized in this research. Ferrites have high absorbing potential in visible regions and fast movement of charge carrier species. Therefore, the ferrites are potentially used in photocatalysis to purify contaminated water. Graphitic carbon nitride shows enhanced separation of charges, which lowers the rate of recombination of charge carrier species. Lithium nickel ferrite, lithium nickel ferrite doped with terbium, and its composite with graphitic carbon nitride (g-C3N4) are synthesized by sol-gel and ultra-sonication methods, respectively. The prepared samples are analyzed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), Electrochemical impedance spectroscopy (EIS), and Mott-Schottky analysis. The bandgap of LiNiFe2O4 and LiNiTbFe2O4 was 2.35 eV, and 1.87 eV, respectively. LiNiTbFe2O4@g-C3N4 degraded 86 % crystal violet and 83 % rhodamine B in 120 min. The LiNiTbFe2O4@g-C3N4 composite showed the maximum degradation and can be potentially used in wastewater treatment.