Zinc titanates nanopowders: synthesis and characterization

Zinc titanates nanopowders viz.; Zn2TiO4, ZnTi3O8 and ZnTiO3 were synthesized through the thermal decomposition course of ZnC2O4.2H(2)O-TiO2 precursors mixture (1:1 mole ratio), prepared via a new co-precipitation method up to 900 degrees 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 degrees C via detecting Zn2TiO4 along with ZnO and TiO2 (anatase) diffraction peaks. By increasing the calcination temperature to 800 degrees C, the ZnO content vanished with the appearing of Zn2Ti3O8 besides ZnTi2O4 and impurities of TiO2 (anatase). Finally at 900 degrees C, the Zn2Ti3O8 content was decomposed into ZnTiO3. Nitrogen adsorption-desorption isotherm of the calcined precursors mixture at 900 degrees 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 degrees C-308 degrees C. The obtained low dielectric value suggests the uses of present titanates as a co-fired ceramic or resonator ceramics.