Structural and Magnetic Behavior of BaAl{sub x}Cr{sub y}Fe{sub 11}O{sub 19} (x + y = 1) Hexagonal Ferrites

The present study aims to analyze barium hexagonal ferrite and its derivation behavior using sol-gel auto-combustion co-doped with Al{sup 3+}/Cr{sup 3+}ions. Also, the effects of dopants on structural and magnetic properties of prepared samples were investigated. To this purpose, the finest powders were preheated at 500 °C for 1 h and calcinated at 900 °C about 2 h. Then, the magnetic powders were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and vibrating sample magnetometer (VSM). The XRD patterns show the magnetoplumbite phase. According to the Scherrer equation applied, inserting ions led to a decrease in lattice parameters (a and c) and crystallite size. The morphology of synthesized samples was observed by FESEM and proved the hexagonal shapes of the prepared samples. The nanoparticles sizes were recorded between 59 and 79 nm. Moreover, the magnetic properties of prepared samples were specified by VSM. The saturation magnetization (M{sub s}) and remnant magnetization (M{sub r}) of the synthesized magnetic powders were decreased by inserting Al{sup 3+}/Cr{sup 3+} ions, while coercivity (H{sub c}) increased from 5215 to 7178 Oe. .