Structural, electrical, dielectric, magnetic, and microwave absorption properties of Cr substituted BaSrCo2Fe12O22 hexaferrites for high-frequency applications

Abstract

In the recent decade, advancements in technology and the excessive use of electronic devices in everyday life have harmed human health and produced electromagnetic pollution. To overcome these problems, hexagonal ferrites are used as excellent microwave-absorbing materials to clean the environment and protect human health. In this study, chromium (Cr3+) substituted Y-type BaSrCo2CrxFe12-xO22 hexaferrites (x = 0.0, 0.5, 1.0, 1.5, and 2.0) have been synthesized through self-ignited sol-gel method and sintered at 1150 °C for 5.5 h. The single phase of the synthesized nanomagnetic materials was confirmed by X-ray diffraction analysis. FTIR analysis unfold the Fe–O vibrational bands at tetrahedral and octahedral sites due to iron oxide base material. The incorporation of Cr3+ limits the transfer of electrons. As a result, DC electrical resistivity significantly increases from 7.59 × 109–4.85 × 1010 (Ω cm). The dielectric behavior and impedance analysis was carried out in the 1 MHz - 6 GHz range. By replacing Cr3+, the dielectric constant and loss exhibit a decreasing behavior. For all compositions, the values of reflection loss are calculated in the range of −39.37 to −32.95 to make them excellent microwave-absorbing materials due to their lower cost, small size, and lightweight properties. The substitution of Cr3+ increases the saturation magnetization (61.35–96.10 emu/g), coercivity (62.31–897.99 Oe), and remanence (12.30–46.52 emu/g). An increase in the coercivity value indicated that samples are thermally stable and suitable for perpendicular magnetic recording media.