Synthesis and Characterization of Composites with Y-Hexaferrites for Electromagnetic Interference Shielding Applications.

The current research is focused on the chemical process and characterization of Co-based Y-type hexaferrite, electrochemically active polypyrrole doped with dodecylbenzene sulphonicacid (PPy-DBSA) and their composites. The microemulsion technique was used to produce hexaferrite with the formula Sr₂Co₂Fe₁₂O₂₂. The resistivity of pure ferrite specimens was 103 ohm-cm, which was lower than the 106 ohm-cm resistivity of the monomer utilized in the polymerization operation. As the temperature increases, the DC resistance decreases, revealing the specimens' semiconductor nature. The cole-cole plots have been used to assess whether significant grain boundaries were involved in the dielectric relaxation process. By increasing the frequency, the electrochemical performance of all specimens was enhanced. Using the rate equation, ionic conductivity demonstrates that polarons are responsible for conduction. Because of the characteristics of the polymer PPY-conducting DBSA, the composites PPY/DBSA + Sr₂Co₂Fe₁₂O₂₂ exhibit a higher dielectric loss of 35 at 1 MHz. This specimen is perfect for electrical radiation shielding (EMI).These ferrites are widely used as permanent magnets, in microwave devices, high-density perpendicular media, and rigid disk media without lubricant and protective layers. [ABSTRACT FROM AUTHOR]