Fabrication and photocatalytic property of magnetic SrTiO 3 /NiFe 2 O 4 heterojunction nanocomposites.

Novel multifunctional SrTiO 3 /NiFe 2 O 4 nanocomposites were successfully fabricated via a two-step route. The as-prepared samples were characterized by using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), field-emission transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and vibrating sample magnetometry (VSM). The results indicate that the SrTiO 3 /NiFe 2 O 4 heterostructures are composed of SrTiO 3 spheroidal nanoparticles adhered to NiFe 2 O 4 polyhedra. The heterojunction established in the composite material accelerates the process of electron-hole pair separation and boosts the photo-Fenton reaction. Among the samples, 15 wt% SrTiO 3 /NiFe 2 O 4 nanocomposites exhibit a powerful light response and excellent room temperature ferromagnetism. Subsequently, the photocatalytic degradation of RhB over the as-prepared samples was investigated and optimized, revealing that the 15 wt% SrTiO 3 /NiFe 2 O 4 nanocomposites exhibit the best photocatalytic activity and stability under simulated solar light irradiation. Furthermore, according to experimental results, the possible mechanism of improved photocatalytic activity was also proposed.