Photodegradation of methylene blue by a ternary magnetic TiO2/Fe3O4/graphene oxide nanocomposite under visible light

In this study, a facile hydrolysis method was employed for the synthesis of magnetic TiO2/Fe3O4/Graphene oxide nanocomposites with different amounts of graphene oxide (0.015, 0.03, 0.06, and 0.12 gr), which can be easily separated by application of an external magnetic field. The prepared nanocomposites were evaluated using XRD, FTIR, FESEM/EDX, TEM and UV-Vis DRS techniques. Morphological characterization showed that size of TiO2 nanoparticles (NPs) and Fe3O4 NPs is nearly 6.0-7.0 nm and 27.81 nm, respectively, and they both are coated on the surfaces of graphene oxide. XRD results indicated the presence of anatase TiO2 and inverse cubic spinel Fe3O4 in the nanocomposite structure. Photoactivity of the synthesized nanocomposites in degradation of methylene blue (MB) was investigated by UV irradiation and visible light. According to the results, ternary nanocomposite containing 0.12 gr of graphene oxide can provide the highest photocatalytic MB degradation. Degradation percentages (DP%) of similar to 82% under UV irradiant and 76% under visible light were achieved after 90 min irradiation. Therefore, it is possible to use TiO2/Fe3O4/GO nanocomposite in the photodegradation of MB and other organic pollutants owing to its noticeable visible light-induced photocatalytic performance and also magnetic properties (which help their recycle).