A series of polycrystalline spinel ferrites with the composition
Cd_0.4Mn_0.6Co_xFe_2-xO₄, (x=0.00, 0.125, 0.25, 0.375, 0.5, 0.75, and 1.00) were
prepared by the standard ceramic method to study the effect of Co³⁺ ions
substitution on their AC electrical conductivity and dielectric properties at
different frequencies and temperatures. It was found that the electrical
conductivity decreases as Co³⁺ ions substitution increases. The results obtained
reveal a semiconductor behavior of these samples. Dielectric constant and
dielectric loss were explained with the aid of Maxwell-Wagner and Koop's
model. The electrical conductivity was explained on the basis of the hopping
conduction mechanism.