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

• Main Authors: Aziz, A.A., Puma, G.L., Ibrahim, S., Saravanan, P.
• Format: Article
• Language: English
• Published: 2013
• Subjects: T Technology (General); TA Engineering (General). Civil engineering (General)
• Online Access: http://eprints.um.edu.my/9437/1/Preparation%2C_characterisation_and_solar_photoactivity_of_titania_supported_strontium_ferrite_nanocomposite_photocatalyst.pdf; http://eprints.um.edu.my/9437/; http://www.scopus.com/inward/record.url?eid=2-s2.0-84873915258&partnerID=40&md5=c2075078b5c7bfe1d708f62517d1293c http://www.tandfonline.com/doi/abs/10.1080/17458080.2012.675087 http://www.tandfonline.com/doi/pdf/10.1080/17458080.2012.675087

Enhanced ferromagnetic and visible light active titanium dioxide (TiO2) photocatalyst was synthesised by depositing a hard ferromagnet strontium ferrite (SrFe12O19) onto TiO2 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 TiO2. 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 TiO2) under higher illuminance of sunlight. Likewise under diffused sunlight, 100% degradation of 2,4-DCP was achieved in 240 min for the supported TiO2, while ≥90% degradation could be achieved in 300 min for the unsupported TiO2. The supported nanocomposite was recycled under a permanent magnetic field with a mass recovery of 98% and reused. © 2013 Copyright Taylor and Francis Group, LLC.