Efficient solar light-driven degradation of Congo red with novel Cu-loaded Fe₃O₄@TiO₂ nanoparticles

In this work, Cu-loaded Fe₃O₄@TiO₂ core shell nanoparticles were prepared in a single pot by coating of TiO₂ on Fe₃O₄ nanoparticles followed by Cu loading. X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), thermogravimetric analysis (TGA), Brunauer-Emmett- Teller (BET), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and valence band X-ray photoelectron spectroscopy (VB XPS) techniques were used for characterization of as prepared nanoparticles. Synergism between copper and titania was evaluated by studying the solar light-driven photodegradation of Congo red dye solution in the presence of Fe₃O₄@TiO₂ nanoparticles on one side and Cu-loaded Fe₃O₄@TiO₂ nanoparticles on the other side. The latter performed better than the former catalyst, indicating the enhanced activity of copper-loaded catalyst. Further photodegradation was studied by three means, i.e., under ultraviolet (UV), refluxing, and solar radiations. Cu-loaded Fe₃O₄@TiO₂ enhanced the degradation efficiency of Congo red dye. Thus, Cu act possibly by reducing the band gap of TiO₂ and widening the optical response of semiconductor, as a result of which solar light could be used to carry out photocatalysis. Graphical abstract Photodegradation of congo red over Cu-loaded Fe₃O₄@TiO₂ nanoparticles.