Copper ferrite nanoparticles supported on MIL-101/reduced graphene oxide as an efficient and recyclable sonocatalyst

The sonocatalytic activity of a novel magnetic CuFe₂O₄/MIL-101/Graphene (CMG) ternary nanocomposite was studied in the removal of some organic dyes (methylene blue, rhodamine B, and methyl orange) from water by using H₂O₂ as a green oxidant. The CMG nanocomposite was prepared at 200 °C, through a two-step hydrothermal route. The physicochemical properties of the synthesized nanocomposite were evaluated using scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, magnetic measurements, atomic force microscopy, Brunauer–Emmett–Teller analysis and Raman microscopy. The excellent sonocatalytic activity of the CMG nanocomposite could be understood by the mechanisms of sonoluminescence and hot spots. The effects of operating parameters such as dye initial concentration, pH and catalyst dosage have also been investigated. Trapping experiments indicated that the sonodegradation of dyes was mainly achieved by hydroxyl radicals (^•OH) attack in the CMG suspension. Benefiting from magnetic property of the CuFe₂O₄ nanoparticles, the CMG nanocomposite could be easily separated from the reaction mixture by a magnet and reused without any change in structure.