Investigation on Impedance Response and Dielectric Properties of La0.7Ca0.3MnO3-CoFe2O4 (LCMO-CFO) Nanocomposite

Abstract

In the present scenario, the toughest and intriguing issue is to find a material with high dielectric constant as well as low dielectric loss at and above the room temperature. To beat these challenges, 70%-La0.7Ca0.3MnO3-30%-CoFe2O4 nanocomposite is prepared via glycine-nitrate auto combustion method. From XRD and FT-IR patterns, the formation of perovskite-spinel structure is clearly visualized. FESEM image displays agglomerated grains due to magnetic nature of the nanocomposite. Impedance and dielectric measurements are carried out in the frequency range 102Hz-106Hz over various temperatures (from room temperature to 100ᵒC). Contributions of diverse nanostructures have been built up by fitting Cole-Cole plot of impedance using R(QRg)(QRgb)(CRin) circuit. Impedance is lowered in a spectacular manner with increase in temperature. Dielectric permittivity increases to the order of 105 in the fabricated system which finds suitability in high frequency devices.