Sonocatalytic performance of magnetically separable CuS/CoFe₂O₄ nanohybrid for efficient degradation of organic dyes

The sonocatalytic activity of the magnetic CuS/CoFe₂O₄ (CuS/CFO) nanohybrid was studied through the H₂O₂-assisted system for degradation of water soluble organic pollutants such as methylene blue (MB), rhodamine B (RhB) and methyl orange (MO). The CuS/CFO nanohybrid was fabricated at 200 °C by hydrothermal method. X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) equipped with energy dispersive X-ray microanalysis (EDX), Fourier-transform infrared spectroscopy (FT-IR), UV–Vis spectroscopy, magnetic measurements, and Brunauere-Emmette-Teller (BET) were employed for the characterizing the structure and morphology of the so-synthesized nanohybrid. Compared with sonolysis/H₂O₂, the higher degradation of MB (25 mg/L) was achieved via sonocatalytic process. The degradation efficiency of sonolysis/H₂O₂, sonocatalysis using CuS/H₂O₂, CFO/H₂O₂ and CuS/CFO/H₂O₂ systems was 6%, 62%, 23% and 100% within reaction time of 30 min for MB, respectively. The integration of H₂O₂ and catalyst dosage intensified the sonocatalytic degradation of MB. On the other hand, adding a hydroxyl radical ([rad]OH) scavenger (tert-butyl alcohol) and a hole scavenger (disodium ethylenediaminetetraacetate) decreased the degradation efficiency from 100% to 35% and 72% within 30 min, indicating the [rad]OH radicals as prominent oxidizing agent of this process. Furthermore, the magnetic property of the sample helped for easier separation of the nanohybrid, made it recyclable with a negligible decline in the performance even after four consecutive runs.