Synthesis of a novel heterogeneous fenton catalyst and promote the degradation of methylene blue by fast regeneration of Fe2+

A novel heterogeneous catalyst (TEA/GO@Fe3O4) was synthesized by simple one-step hydrothermal method. Surprisingly, TEA/GO@Fe3O4 showed an extremely fast decomposition rate for methylene blue (MB). According to the characterization results, the superior properties of the TEA/GO@Fe3O4 can be attributed to following factors: (1) the application of GO prevents the agglomeration of Fe3O4 nanoparticles, (2) the delocalized electrons of GO and the lone pair electrons of triethanolamine and its oxidant products (TEA) promoted the regeneration of Fe-2(+), (3) the negative surface charge of TEA/GO@Fe3O4 and the coordination between Fe and S can accelerate the diffusion rate of MB toward the surface of catalyst, (4) the prepared materials were superparamagnetic with a negligible coercivity and remanence, (5) the Fe3O4 nanoparticles were immobilized on the surface of GO and functionalized by the TEA. Finally, the presumption mentioned above was proved by TEM, FTIR, XRD, XPS, Zeta potential and the degradation experiments. After the degradation reaction, the catalyst can be quickly separated by external magnetic field. Therefore, the TEA/GO@Fe3O4 is a promising catalyst for the degradation of MB.