L and S band microwave absorption properties of Z-type hexaferrite Ba3Co2Fe24O41 synthesized at low temperature

The L-band and S-band electromagnetic waves are widely utilized in radar and satellite communications. This paper reports the successful synthesis of 85.8% content Ba3Co2Fe24O41 (Co(2)Z) at a relatively low temperature of 1150 degrees C using the solid-phase method with BaFe12O19 (BaM) and Ba2Co2Fe12O22 (Co2Y) as precursors. The Co(2)Z samples were confirmed to have been successfully synthesized using X-ray diffraction (XRD) and thermogravimetry/differential scanning calorimetry (TG-DSC) spectra. Scanning electron microscopy (SEM) images revealed that the sintered samples exhibited large grains (>10 mu m). Vibrating-sample magnetometry (VSM) data indicated that the synthesized Co(2)Z samples possessed distinct soft magnetic properties. X-ray photoelectron spectroscopy (XPS) results showed that the Fe3+ content decreased with the increase in synthesis temperature. The samples synthesized at 1110 degrees C - 1280 degrees C had a permeability of 10-20, a cut-off frequency of approximately 1 GHz, and a dielectric constant of 10-30. When the thickness of the sample synthesized at 1150 degrees C was 3.9 mm, the frequency range of the reflection loss (RL)< -10 dB was 2.55 GHz (0.98-3.53 GHz), with 1.77 GHz as the center frequency, and RLmin was - 57.8 dB. This observation indicates that the effective absorption bandwidth of the samples covers the entire L and S bands, which significantly satisfies practical applications within the military and civilian sectors.