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ZnO/TiO2 composite ceramics have been prepared by solid‐state reaction technique at 900°C. The X‐ray diffraction results revealed the formation of secondary phases referred to as spinel Zn2TiO4 and hexagonal ZnTiO3. The structural analysis showed that all the composites that have been prepared have a polycrystalline nature and a hexagonal wurtzite structure. The complex modulus (M) and electric impedance of the samples have been investigated by broadband dielectric spectroscopy in a wide range of temperature (40°C‐110°C) and frequency (0.1 Hz to 10 MHz). The modulus plots (M′′, M′) illustrate the presence of non‐Debye type of relaxations attributed to the effects of interfacial and dipolar polarizations. The real and the imaginary parts of the impedance are well fitted to equivalent circuit models. At high temperatures, Z″max varies from 0.03 × 106 to 4.9 × 106 Ω when the TiO2 doping concentration increases from 1 to 7 wt%. From the obtained results, the secondary phase ZnTiO3 plays an important role in the electrical properties.

Undoped zinc oxide (ZnO) has been prepared at various growth temperatures by conventional sintering process. The morphology and crystalline properties of ZnO pellets were examined by scanning electron microscopy, atomic force microscopy and X-ray diffraction. It has revealed that the grain size and surface roughness tends to increase by increasing the sintering temperature. XRD analysis showed that all samples are polycrystalline with a hexagonal wurtzite structure. The alignment of ZnO grains along the (10.0) plane was enhanced as the temperature increased. Interestingly, the compressive stress was found to decrease drastically from –0.62 GPa at 700°C to –0.2 MPa at 1000°C. This improvement in film structure seems to enhance considerably the dielectric properties for the samples sintering at high temperatures. Results show an increase of dielectric constant and a decrease of electrical resistivity when increasing the sintering temperature