A study on the conductivity, dielectric, and microwave properties of SrNbxYxFe12-2xO19 (0.00 ≤ x ≤ 0.05) nanohexaferrites

Abstract

In this paper, conductivity, dielectric, and microwave properties of SrNbxYxFe12-2xO19 (0.00 ≤ x ≤ 0.05) hexaferrites (SrNbY HFs) synthesized by the citrate sol–gel method were investigated. Some key parameters compatible with the electrical and dielectric functions of SrNbY HFs have been extensively evaluated as functions of bias frequency, measurement temperature, and co-substitution ratios in logarithmic 3D graphs by complex impedance spectroscopy. It has been observed that although the co-substitution ratio is highly functional on dielectric parameters such as both the dielectric constant and dielectric loss, as well as the dissipation factor, it has a very low influence on the conductivity mechanism. Depending on the substitution ratios of Nb and Y ions and the transition temperature region, the activation energy was calculated to vary between 58 and 476 meV. Microwave properties were measured as S-parameters using a coaxial line in the range of 2–12 GHz. It was analysed the frequency dependences of the real/imaginary parts of the permittivity and permeability for all samples. Reflection losses vs. frequency were calculated as a function of the substitution level. Coefficients of the RL (−12.5 … −16.8 dB) confirm practical importance for electromagnetic compatibility at high frequencies.

Keywords

• Hexaferrites
• Conductivity
• Dielectric properties
• Microwave absorber