Fabrication of magnetic recoverable Fe3O4/TiO2 heterostructure for photocatalytic degradation of rhodamine B dye

Abstract

Magnetic photocatalysts are crucial for creating a feasible photocatalytic technique for the degradation of organic contaminants due to the ease of photocatalyst separation and recycling. In this study, magnetic Fe3O4/TiO2 nanocomposites as an effective and recyclable photocatalyst with different Fe3O4 loading percentages were successfully synthesized by a hydrothermal method. The physicochemical properties of the synthesized materials were characterized using XRD, FTIR, BET, TGA, TEM, EDS, XPS, PL, and UV − vis DRS. The nanocomposite poses a higher BET surface area (164.76 m2/g,) than TiO2 (177.67 m2/g) due to the synergistic effect and interface between the two different oxides. The optical properties results showed that the incorporation of magnetite Fe3O4 to TiO2 nanoparticles shifted the light absorption of TiO2 from ultraviolet (UV) to the visible region and postponed the electron-hole recombination. The synthesized photocatalysts were used for photocatalytic degradation of rhodamine B as the model pollutant under simulated solar light irradiation. The maximum degradation efficiency of 91% was achieved after 120 min using 20% FT nanocomposite. The enhanced photocatalytic activity of 20% FT nanocomposite was attributed to the high surface area, increased light absorption, and formation of heterojunction structure which promotes the separation efficiency of photogenerated electron-hole pairs. The photocatalyst maintained good stability with a 3% loss in efficiency after 5 cycles of re-use. Scavenger trapping assays showed that the main active species for the degradation of RhB are hydroxyl radicals. Moreover, the effect of Fe3O4 loading, solution pH, photocatalyst dosage, rhodamine B concentration, and reusability of the photocatalyst on the degradation efficiency of dye pollutants were studied. The results attained in this study suggest that stable magnetic recoverable photocatalysts could be used to remediate organic water pollutants and can be extended to environmental samples application.