| Summary: | Zinc titanates nanopowders viz.; Zn _2 TiO _4 , ZnTi _3 O _8 and ZnTiO _3 were synthesized through the thermal decomposition course of ZnC _2 O _4 .2H _2 O-TiO _2 precursors mixture (1:1 mole ratio), prepared via a new co-precipitation method up to 900 °C. Thermogravimetric measurement (TG) was utilized to characterize the precursors mixture decomposition while x-ray diffraction (XRD), Fourier transform infra-red (FT-IR) were used to characterize the decomposition products as well as the phase transitions at different temperatures. XRD revealed the starting of titanates formation at 700 °C via detecting Zn _2 TiO _4 along with ZnO and TiO _2 (anatase) diffraction peaks. By increasing the calcination temperature to 800 °C, the ZnO content vanished with the appearing of Zn _2 Ti _3 O _8 besides ZnTi _2 O _4 and impurities of TiO _2 (anatase). Finally at 900 °C, the Zn _2 Ti _3 O _8 content was decomposed into ZnTiO _3 . Nitrogen adsorption-desorption isotherm of the calcined precursors mixture at 900 °C indicated low specific surface area of 7.1 m ^2 g ^−1 in accordance with the agglomeration nature estimated via transmission electron microscopy (TEM) study. The conductivity measurements showed semiconducting behavior of the prepared titanates with ferroelectric transition in the range 200 °C–308 °C. The obtained low dielectric value suggests the uses of present titanates as a co-fired ceramic or resonator ceramics.
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