New TiO2-doped Cu-Mg spinel-ferrite-based photocatalyst for degrading highly toxic rhodamine B dye in wastewater.

The quest for finding an effective photocatalyst for environmental remediation and treatment strategies is attracting considerable attentions from scientists. In this study, a new hybrid material, Cu0.5Mg0.5Fe2O4-TiO2, was designed and fabricated using coprecipitation and sol-gel approaches for degrading organic dyes in wastewater. The prepared hybrid materials were fully characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results revealed that the Cu0.5Mg0.5Fe2O4-TiO2 hybrid material was successfully synthesized with average particle sizes of 40.09 nm for TiO2 and 27.9 nm for Cu0.5Mg0.5Fe2O4. As the calculated bandgap energy of the hybrid material was approximately 2.86 eV, it could harvest photon energy in the visible region. Results indicate that the Cu0.5Mg0.5Fe2O4-TiO2 also had reasonable magnetic properties with a saturation magnetization value of 11.2 emu/g, which is a level of making easy separation from the solution by an external magnet. The resultant Cu0.5Mg0.5Fe2O4-TiO2 hybrid material revealed better photocatalytic performance for rhodamine B dye (consistent removal rate in the 13.96 × 10-3 min-1) compared with free-standing Cu0.5Mg0.5Fe2O4 and TiO2 materials. The recyclability and photocatalytic mechanism of Cu0.5Mg0.5Fe2O4-TiO2 are also well discussed.