Investigate structural, morphological, electrical, dielectric and magnetic properties of dysprosium doped Cobalt-Nickel ferrites and their response to gamma irradiation

Abstract

Nanocrystalline Co1-xNixFe2-yDy0.5O4 ferrites were successfully prepared by the sol–gel auto-combustion method. The samples were gamma-irradiated using a cobalt-60 source. XRD analysis reveals the formation of cubic spinel structure. FTIR study is used to confirm the formation of the expected spinel ferrite structure. Two probe method was used to measure DC electrical resistivity and the Arrhenius relation was used to calculate activation energy for non-irradiated and irradiated ferrites. Frequency dependent dielectric properties of the non-irradiated and irradiated ferrites were studied at room temperature. The dielectric constant for most of the gamma-irradiated samples increases because defects are induced in the material which increases space charge polarization in the samples. Magnetic properties of non-irradiated and irradiated nano ferrites were studied using VSM. Coercivity decreases after irradiation because decrease in grain size which increases surface state pinning of the domains.