Photocatalytic activity and magnetic properties of nanocrystallite strontium hexaferrite prepared by self-flash combustion

Abstract

AbstractStrontium hexaferrite is a promising material for magnetic nanoscale applications owing to its high coercivity and saturation magnetisation. Nanocrystallite strontium hexaferrite was prepared by self-flash combustion of acetate precursors. A 2 : 1 molar ratio of iron acetate to strontium acetate in the precursor was found to give a 50 : 50 product of strontium monoferrite and strontium hexaferrite, whereas a single phase, strontium hexaferrite, was obtained at a 8 : 1 molar ratio. The powder obtained was fired at 600°C for 2 h, to assist decomposition of acetates, then pressed into compacts and sintered at 850°C for 2 h to ensure complete transformation to the hexaferrite phase. The nanocrystalline (90 nm) strontium hexaferrite and strontium monoferrite (50 nm) crystals obtained were characterised by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry, differential thermal analysis, transmission electron microscopy and light microscopy. Magnetic properties measured by vibrating sample magnetometry showed promising values for Hc, Br and Bs. The photocatalytic activity of the strontium hexaferrite in the degradation of Toludine blue dye was studied. Complete degradation of the dye was achieved after 20 h under illumination under a tungsten lamp.Keywords: NANOCRYSTALLINE MATERIALSSTRONTIUM HEXAFERRITEPHOTOCATALYSISMAGNETIC PROPERTIESTOLUDINE BLUE DYE