Structural, electric and dielectric properties of Ca0.85Er0.1Ti1−xCo4x/3O3(0 ≤ x ≤ 0.1)

The structural and physical properties of Ca0.85Er0.1Ti1−xCo4x/3O3 (CETCox) (x = 0.00, 0.05 and 0.10), synthesized by sol–gel method were studied. The polycrystalline sample of CETCox was investigated by X-ray diffraction and morphological properties by scanning electron microscopy (SEM) as well as the electrical characterizations. A single orthorhombic perovskite structure with a Pbnm space group was obtained. The electrical properties were studied by impedance complex spectroscopy in the frequency range (102–107 Hz) at different temperatures. The electrical properties showed that all samples have a semiconductor behavior. Conductivity decreased with increasing Co rate. At a specific temperature, a saturation region was marked in the conductivity curve as a function of temperature. From the curve of the average normalized change with temperature dependence, we deduced the temperature in which the density of trapped charge is vanished, confirming the saturation which appears at the temperature dependence of conductivity. The complex impedance analysis confirmed the existence of electrical relaxation in the materials, which may be responsible for the electrical conduction. CETCox presented a decrease of the real and imaginary part of permittivity and dielectric loss with increasing frequency. This can be explained by Maxwell–Wagner type of polarization in accordance with Koop’s theory and can also explain the increase of conductivity with frequency.