Electrostatic self-assembly of Fe₃O₄/GO nanocomposites and their application as an efficient Fenton-like catalyst for degradation of rhodamine B

In the study, a two-major step involving a hydrothermal method and an electrostatic self-assembly method was adopted to synthesis Fe₃O₄/GO nanocomposites. The Fe₃O₄ nanoparticles were successfully modified with the 3-aminopropyltrimethoxy-silane and homogeneously deposited onto the surface of GO. They were used as Fenton-like catalyst to degrade Rhodamine B and displayed a higher activity compared with the pristine Fe₃O₄ nanoparticles, H₂O₂, Fe₃O₄/GO nanocomposite and Fe₃O₄/H₂O₂ system, demonstrating the synergistic effect between the superior adsorption properties of GO and the excellent catalytic activity of Fe₃O₄/H₂O₂ system. Besides, the possible catalytic mechanism and degradation pathway for RhB molecules by Fe₃O₄/GO nanocomposites and H₂O₂ was proposed based on the liquid chromatography-mass spectrometry (LC-MS) analysis. The result reveals that the •OH radicals should be the main actives species during catalytic degradation of RhB by the Fe₃O₄/GO/H₂O₂ system. In addition, the catalyst is reusable and shows efficiency up to 5 cycles. We believe the strategy in our work can provide insight into designing the novel catalysts for large-scale degradation of organic pollutants in the wastewater. (paper)