Structure, Dielectric Permittivity, and AC Conductivity of Cobalt and Lanthanum Doped TiO2 Composites

Lanthanum doped titanium dioxide (La/TiO2) was synthesized by a lengthy wet impregnation method with cobalt (Co/TiO2). The prepared composites were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The XRD spectrum of TiO2 shows that the transition dopants are well dispersed within the TiO2 matrix. The SEM images show no noticeable morphological differences between the TiO2, La/TiO2, and Co/TiO2 composites. The dielectric properties and electrical of TiO2, La/TiO2, and Co/TiO2 were investigated within temperature and frequency of 25–120 °C and 100 Hz to 0.3 MHz, respectively. It was noted that the dielectric constant decreases with increasing temperature. TiO2 dielectric permittivity and electrical conductivity increased as a result of doping. In addition, the activation energy values for all samples were evaluated. By increasing frequency, activation energy values decreased and this decrease intensified when the Co ions are the substituents in the TiO2 matrix. Otherwise, the values of activation energy are constant for La-dopedTiO2.