The effect of doping of Mn on structural and magnetic properties of the strontium hexaferritenanoparticels

In this research, the SrMnxFe12-xO19 nanoparticles with x = 0.0, 0.5, 1, 1.5 and 2 at 1000 oC  for 4 h, using sol-gel method, were synthesized. Thermal analysis, crystalline structure and their bonding properties of the samples by TGA / DTA analysis, XRD and FT-IR were investigated. In order to investigate morphology of the samples from field emission, scanning electron microscopy (FESEM) was used. Also, properties of the samples, using vibrating sample magnetometer (VSM), were investigated. In addition to the Curie temperature of SrMnxFe12-xO19 nanoparticles with x = 0.0, 0.5 and 1 was determined. Thermalgravimetric analysis confirms that the formation of the hexagonal phase at temperature of 953.1 oC. The results of measurements of the XRD show that the phase percentage of SrMnxFe12-xO19 nanoparticles with x = 0.5 has increased. The results of the hysteresis loops of SrMnxFe12-xO19 nanoparticles reveal that with increasing Mn contents, the saturation magnetization, remanence magnetization and magnetic coercivity reduced. Also, the results of the magnetization of SrMnxFe12-xO19 nanoparticles with temperature reveal that with increasing of Mn contents, the Curie temperature decreased.