Magneto-optical properties and physical characteristics of M-type hexagonal ferrite (Ba1-xCaxFe11.4Al0.6O19) nanoparticles (NPs)

The preparation of metal oxide nano materials with higher magnetization and improved coercivity is crucial for microwave absorber, radar, and antenna applications. Therefore, M-type hexagonal ferrite samples with the composition of Ba1-xCaxFe11.4Al0.6O19 (x = 0, 0.33, 0.66 and 1.0) are prepared by the sol-gel auto-combustion approach. X-ray diffraction (XRD) confirms the M-type hexagonal phase of the prepared samples, whereas scanning electron microscopy (SEM) explains the morphology, agglomerations, and grain size of the synthesized nanoparticles (NPs). The measured grain size of prepared NPs is in the range of 0.19 to 0.098 mu m. Fourier transform infrared (FTIR) confirms that the hexagonal phase formation and obtained force constant is in 649.11 cm(-1) to 760.46 cm(-1) range. The UV?Vis spectroscopy explains the semiconducting nature of the prepared hexaferrite samples. The magnetic analysis such as saturation magnetization (M-s) and remanence (M-r) of the prepared M-type hexagonal ferrite NPs increases from 46.652 to 50.363 emu/g and 18.724-23.745 emu/g, respectively. The coercivity of the prepared M-type hexagonal ferrite is in the range of 633.245-1633.236 Oe. The temperature dependent DC conductivity (sigma(DC)) of the M-type hexagonal ferrite NPs is evaluated from room temperature (273 K) to 743 K temperature range and increasing trend in sigma(DC) has observed with the rise of temperature.

Automated summary

Nano-sized metal oxide materials with higher magnetization and improved coercivity were prepared using sol-gel auto-combustion approach. The synthesized samples exhibited M-type hexagonal phase with fine magnetic properties and semiconductor characteristics, making them potential candidates for various applications such as microwave absorbers and radar systems.