Effect of Non-aqueous Media on Nano-crystalline SrFe12O19 Particles Produced by Co-precipitation with Metal Chlorides and Evaluation of Their Magnetic and Photocatalytic Properties

Abstract

The strontium ferrite nano-crystals were prepared via co-precipitation method in different synthesis media including a mixture of ethanol and water (with a volume ratio equal to 3:1) and water. In this way, the iron and strontium chlorides with various molar ratios were utilized as sources for Fe3+ and Sr2+ ions, respectively. Phase analyses, structural properties and morphology of the SrFe12O19 powders were characterized by various techniques including X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer and Fourier transform infrared spectra. Thermal decomposition behaviors of the as-synthesized precursors were monitored by DTA/TGA (differential thermal analysis/thermo-gravimetric analysis). The effects of molar ratio, calcination temperature and co-precipitation media of the strontium ferrite powder were investigated. The results of DTA indicated that the strontium hexaferrite prepared by co-precipitation in ethanol/water media was formed at a lower temperature. The maximum saturation magnetization of the strontium ferrite powder with the value of 58 emu/g was achieved at a temperature of 950 °C by a Fe3+/Sr2+ molar ratio of 12. Wide coercivity in the range of 1512–5764 Oe was observed by tuning calcination temperatures. Furthermore, the photocatalytic properties of the resultant optimum SrFe12O19 particles were assessed. The destruction of methylene blue dye was about 46% in the presence of the strontium ferrite under UV light irradiation for 120 min.