Degradation of methylene blue with a novel Fe3O4/Mn3O4/CuO nanomaterial under sonocatalytic conditions

In this study, Fe3O4/Mn3O4/CuO nanoparticles were synthesized, characterized, and used as a nanocatalyst in methylene blue (MB) degradation under ultrasonic conditions. The synthesis of Fe3O4/Mn3O4/CuO nanoparticles was carried out according to a facile method and characterized using some analytical techniques such as FTIR, scanning electron microscopy (SEM) with transmission electron microscopy (TEM), EDS, and X-ray diffraction (XRD). The obtained Fe3O4/Mn3O4/CuO nanoparticles showed a very homogeneous structure, and the average particle size was determined as 1.87 nm. XRD analyses revealed that Fe3O4/Mn3O4/CuO nanoparticles have a 2.27 nm crystalline particle size. The chemical composition of Fe3O4/Mn3O4/CuO nanoparticles was well detected by FTIR and SEM-EDS analyses. The products formed after the degradation of MB were detected by gas chromatography-mass spectrometry (GC-MS). The degradation of MB was investigated with several experimental conditions using Fe3O4/Mn3O4/CuO nanoparticles, and optimum experiment conditions were detected to be [T] = 301 K, [MB] = 0.03 g/L, [Cat.] = 1.0 g/L, [H2O2] = 5 mM, [Ult.] = 60 kHz. A maximum of 95.04% MB degradation using Fe3O4/Mn3O4/CuO nanoparticles was achieved in 150 min. To detect the radical effectiveness, t-butanol, ethanol, and t-butanol scavenger solvents were tested, and it was detected that these scavenger solvents prevent the formation of radicals that are effective in MB degradation. As a result, the present work paves the way to prepare excellent and highly efficient sonocatalysts for the degradation of organic dyes.