Synergistic effects of Li-based ferrite and graphene oxide in microwave absorption applications

The successful fabrication of composites consisting of ferrites with a composition of Li_0.4Mg_0.25Zn_0.25Fe_2.2O₄ and Graphene oxide was carried out using the ultra-sonication technique. The current study examined the impact of graphene oxide in spinel ferrite employing X-ray diffraction, dielectric, and magnetic susceptibility studies. The X-ray diffraction investigation confirmed the spinel phase formation in ferrite and graphene oxide synthesis. The measured range for the size of crystallites was found to be between 48.43 and 30.07 nm. The DC resistivity of cubic ferrite at room temperature was determined to be 1.715 ×10¹⁰ ohm-cm by a two-probe approach. Furthermore, it was observed that the resistivity fell significantly as the content of graphene oxide increased. The dielectric constant exhibited behavior consistency with the Maxwell-Wagner phenomenon of interfacial polarization. The rise in graphene oxide content in ferrite results in high AC conductivity of composites due to the relatively large value of conductivity of graphene oxide and the improved charge hopping mechanism. The magnetic susceptibility of all the samples demonstrated a progressive decline as the temperature increased, which can be attributed to the disruption of spin alignment at the Curie temperature. The observed Curie temperature of all samples was 413–473 K. Integrating spinel ferrite with Graphene oxide has significantly improved the magneto-electrical characteristics, indicating potential applications in supercapacitors, high-frequency electromagnetic devices, and microwave absorption.