Preparation, characterisation and solar photoactivity of titania supported strontium ferrite nanocomposite photocatalyst

Enhanced ferromagnetic and visible light active titanium dioxide (TiO 2 ) photocatalyst was synthesised by depositing a hard ferromagnet strontium ferrite (SrFe 12 O 19 ) onto TiO 2 via an effortless hydrothermal and poly-condensation method.The catalysts were characterised by X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDS), BET surface analysis, vibrating sample magnetometer (VSM), X-ray photon spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and UV-visible light spectroscopy analysis.The prepared nanocomposite photocatalyst exhibited physically a powerful ferromagnetic property with significant stability against the loss of its magnetic property (coercivity 2200 G).The catalyst can be fluidised and recovered by an external magnetic field enhancing separation and mixing efficiency.Furthermore, it resulted in a reduced band gap (2.3 eV) which resulted in enhanced visible light absorption compared with unsupported TiO 2 .The photocatalytic activity was investigated by degrading a recalcitrant phenolic compound, viz., 2, 4-dichlorophenol (2,4-DCP) as model pollutant under different illuminance of daylight.Complete degradation of 2,4-DCP (50 mg/L initial concentration in 0.25 L) was achieved in 120 min (supported photocatalyst) and 180 min (unsupported TiO 2 ) under higher illuminance of sunlight.Likewise under diffused sunlight, 100% degradation of 2,4-DCP was achieved in 240 min for the supported TiO 2 , while 90% degradation could be achieved in 300 min for the unsupported TiO 2 .The supported nanocomposite was recycled under a permanent magnetic field with a mass recovery of 98% and reused.