Magnetically recyclable MnFe₂O₄/polyaniline composite with enhanced visible light photocatalytic activity for rhodamine B degradation

抄録

The magnetically recyclable MnFe₂O₄/Polyaniline (PANI) composite was successfully synthesized by a combination of a salt-assisted solution combustion method and an in situ oxidative polymerization method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectroscopy (DRS) were employed to characterize the physical and chemical properties of the samples. The results showed that MnFe₂O₄/PANI composite exhibited higher photocatalytic activity and stability than pure PANI and MnFe₂O₄ nanoparticles toward the degradation of rhodamine B (RhB) under visible light irradiation, suggesting the existence of a synergic effect between PANI and MnFe₂O₄. The excited state electrons in the lowest unoccupied molecular orbital (LUMO) of PANI can readily migrate into conduction band (CB) of MnFe₂O₄, while the holes in the valence band (VB) of MnFe₂O₄ migrate to the π-orbital of PANI because of the enjoined electric fields of the two materials, which can further improve the separation of the photoinduced electron–hole pairs.