Dielectric and Magnetic Study of NiCuZn Spinel Ferrites
Reena Sharma, Neelam Hooda, Ashima Hooda, Satish Khasa, Deepak Verma, Harpreet Dhull
Abstract
The ferrite system having spinel structure with composition Ni1-x-yCuxZnyFe2O4; [(x = 0.3, 0.2), (y = 0.2, 0.3, 0.5)] has been amalgamated through solid-state reaction method and structural, dielectric and magnetic studies have been carried out. The Presence of tetrahedral and octahedral bands in FTIR spectra confirmed the proper phase formation of spinel ferrites. In low-frequency region dispersive behaviour has been shown by both dielectric constant (ε') and tangent loss (tanδ) and they show nearly constant value at higher frequencies. This follows Maxwell-Wagner double layer model in which low conductive grain boundaries separate higher conductivity grains and in good agreement with Koop's Model. The Nyquist plot shows depressed semi-circular arcs. The ac conductivity (σac) shows increasing trend with temperature and frequency both. The S parameter has been calculated from the fitted ac conductivity plot and used to explain conductivity mechanism. The samples show good magnetic behaviour. Maximum value of saturation magnetization has been observed for the sample having the highest Zn content. Magnetization versusTemperature plot implies towards non equilibrium magnetization below its reversibility temperature.