Efficient RhB degradation using MnFe2O4/g-C3N4 composites under visible light irradiation

The MnFe2O4/g-C3N4 composites with promising photocatalytic activity were successfully prepared in this study. The structure and morphology of the as-prepared composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), and the photocatalytic activity was evaluated through the degradation of rhodamine B (RhB). It was found that the composites with 30 wt% MnFe2O4 possessed 2.64 times higher photocatalytic activity than that of pure g-C3N4, and the degradation rate of 30 mg/L RhB solution could reach 97.2% in 90 min under 1 sun irradiation. The promising photocatalytic activity of the composites was mainly attributed to excellent adsorption performance and light absorption capacity of the sample. Simultaneously, the recombination of photogenerated electron-hole pairs was delayed due to the formation of heterojunction between MnFe2O4 and g-C3N4, and MnFe2O4/g-C3N4 showed almost no decrease in photocatalytic activity after recycling for five times.