Enhanced magnetodielectric properties of Co2Z ferrite ceramics for ultrahigh frequency applications achieved via Cr3+ ion doping

Phase formation, microstructure, magnetic properties, and dielectric properties of Ba(1.5)Sr(1.5)Co(2)Fe((23-x))CrxO(41) (0.0 <= x <= 1.0) ceramics, in which Fe3+ ions were substituted by Cr3+ ions, were systematically investigated. Xray diffraction results reveal that Z-type hexagonal ferrite was formed by sintering at 1250 degrees C, and Cr3+ ions successfully enter lattice without destroying crystal structure. Analysis of the microstructure reveals that Cr3+ ion doping has significant effect on crystal micromorphology. Samples with x = 0.4 have the most homogeneous micromorphology and the highest sintering density of 5.12 g/cm(3). In addition, under the influence of external magnetic field, all samples exhibit typical soft magnetic character and hysteresis characteristics, with saturation magnetization up to 63.86 emu/g (x = 0.6). Particularly, compared with undoped sample, Cr-doped samples have outstanding magnetic-dielectric properties. Firstly, with increasing Cr3+ amount, real part of the permeability (mu') reaches the maximum value of 10.70 at x = 0.4, while cutoff frequency exceeds 2 GHz, and Snoek constant reaches similar to 19.50 GHz. Furthermore, due to more homogeneous microstructure, samples with x = 0.4 have low magnetic loss and can maintain high quality factor (Q) over a broad frequency range. Moreover, real part of the permittivity (epsilon') reaches the maximum value of 16.90 at x = 0.6, and dielectric loss remains lower than 0.013 for frequencies below 0.7 GHz. Consequently, magnetic-dielectric materials prepared in this work are expected to have extensive application prospects for ultrahigh-frequency devices.

Automated summary

The phase formation, microstructure, magnetic properties, and dielectric properties of Ba(1.5)Sr(1.5)Co(2)Fe((23-x))CrxO(41) (0.0 <= x <= 1.0) ceramics with Fe3+ ions substituted by Cr3+ ions were systematically investigated. The results showed that Z-type hexagonal ferrite was formed with successful incorporation of Cr3+ ions into the lattice. The microstructure analysis revealed that Cr3+ doping had a significant effect on crystal micromorphology, with x = 0.4 samples having the most homogeneous micromorphology and highest sintering density. The Cr-doped samples exhibited outstanding magnetic-dielectric properties, with high permeability and low magnetic and dielectric losses for various frequencies. The materials prepared in this study are expected to have extensive applications in ultrahigh-frequency devices.