The Effect of Ni Doping on the AC Conductivity and Dielectric Properties of Fe-Doped TiO2

Owing to its peculiar physical properties, Titanium Dioxide (TiO2) has found various applications and been an interactive material for research in the field of semiconductor physics. To study the crystallographic nature of prepared Fe/TiO2 and Ni- Fe/TiO2, X-ray Diffraction (XRD) study was done. The result shows that both pure and doped TiO2 samples were anatase phase with the absence of diffraction peaks of Ni or Fe. The Scanning Electron Microscopy (SEM) images revealed that the particle morphology was altered by dopants incorporation which acted as nucleation sites. The dielectric properties and electrical conductivity for TiO2 and TiO2 loaded Fe, Ni and Ni- Fe composition within the temperature range 25°C-110°Cand over the frequency range (100 Hz-0.3 MHz) were also carried out. The values of dielectric constant and dielectric loss decrease with increasing frequency. The dielectric permittivity for Fe/TiO2 exhibits relatively lower dielectric constant than Ni- Fe/TiO2. A relaxation peak has been recognized and shifted to higher frequency with increasing temperature. The ac conductivity was found to increase with frequency which could be related to the hopping conduction process. The activation energy Ea for Fe/TiO2 was higher than Ni-Fe/TiO2 and decreased with increasing frequency.