Layered Ceramic Structures In1+x(Ti1/2Zn1/2)1-xO3(ZnO)m (m = 2, 4 and 6; x = 0.5): Synthesis, Phase Stability and Dielectric Properties

New ceramic materials with layered crystal structures and chemical formula In1+x(Ti1/2Zn1/2)1-xO3(ZnO)m (x = 0.5; m = 2, 4 and 6), here named ITZO-II, ITZO-IV and ITZO-VI, have been synthesized by solid-state reaction method. The phase characterization, phase stability with temperature and their microstructure have been studied by X-ray powder diffractometry (XRD) and scanning electron microscopy (SEM). The XRD showed a hexagonal single phase at 1200 °C whereas, at higher temperatures (1300 and 1400 °C), they decompose in secondary phases such as the In2Zn7O10 solid solution and starting material traces. SEM micrographs showed an increase in grain size as the temperature of sintering increases, reducing the porosity and increasing the bulk density. Here, the dielectric spectra in a wide range of temperatures and frequencies are reported. The permittivity results seem to indicate a classical paraelectric behavior in this class of layered structural ceramic compounds.