Structural and Magnetic Properties of MnxBa0.5-xCo0.5Fe2O4 Nanosized Ferrites

Abstract

This work aims to study the structural and magnetic properties of MnxBa0.5-xCo0.5Fe2O4 nanoparticle powder ferrites (x\u2009=\u20090.1, 0.2, 0.3 and 0.4). The samples were synthesized via glycol-thermal method at $$200^\\circ{\\rm C}$$\n . Single-phase formations for all as-produced samples were confirmed by XRD which revealed cubic spinel structure with space group Fd3m. The average crystallite sizes of the produced compounds ranged from 9.07 to 9.70\xa0nm. HREM images showed that the powder particles are nearly spherical without any agglomeration. 57Fe Mossbauer spectroscopy was used to study local environments of the iron cations at tetrahedral and octahedral sites. Magnetic properties for the as-produced MnxBa0.5-xCo0.5Fe2O4 nanoferrites were investigated using a mini-cryogen free vibrating sample system at different low isothermal temperatures in external applied magnetic fields up to\u2009±\u200950 kOe. The results show that the coercivity increased at lower measuring temperature due to spin freezing. The coercive fields increased from about 0.5 kOe at room temperature for all samples to 8.5 kOe, 11.5 kOe, 5.5 kOe, and 1.8 kOe at 4\xa0K for the samples with $$x=0.1$$\n , $$x=0.2$$\n , $$x=0.3$$\n , and $$x=0.4$$\n , respectively. We also found that the saturation magnetization was affected by spin canting phenomenon. The studied nanoferrites with the obtained structural and magnetic properties could be promising candidate materials for magnetic recording media and memory devices.