Elaboration of nano titania-magnetic reduced graphene oxide for degradation of tartrazine dye in aqueous solution

In this paper, magnetic nanocomposites are synthesized by loading reduced graphene oxide (RG) with two components of nanoparticles consisting of titanium dioxide (TiO2) and magnetite (Fe3O4) with varying amounts. The structural and magnetic features of the prepared composite photocatalysts were investigated by powder X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectra (UV–vis/DRS), Raman and vibrating sample magnetometer (VSM). The resulting TiO2/magnetite reduced graphene oxide (MRGT) composite demonstrated intrinsic visible light photocatalytic activity, on degradation of tartrazine (TZ) dye from a synthetic aqueous solution. Specifically, it exhibits higher photocatalytic activity than magnetite reduced graphene oxide (MRG) and TiO2 nanoparticles. The photocatalytic degradation of TZ dye when using MRG and TiO2 for 3 h under visible light was 35% and 10% respectively, whereas for MRGT it was more than 95%. The higher photocatalytic efficiency of MRGT is due to the existence of reduced graphene oxide and magnetite which enhances the photocatalytic efficiency of the composite in visible light towards the degradation of harmful soluble azo dye (tartrazine). The coupling of Fe3O4 and TiO2 nanoparticles with reduced graphene oxide sheets leads to high photocatalytic activity in degradation of tartrazine under visible light irradiation which reaches more than 95%. This material is important to remediation of water from organic pollutants. [Display omitted] •Magnetic titanium-reduced graphene oxide nanocomposite (NC) was synthesized.•NC was separated easily from solution just by applying an external magnetic field after degradation of organic pollutant.•Magnetite Fe3O4/rGO allowed as well the shifting of the band gap of TiO2 into visible range.•This NC has high photocatalytic activity under visible light.•The degradation of tartrazine reached more than 95%.