Preparation and Electrical Characterization of Zn-Titanate / Borosilicate Glass Composites

Abstract

A Composite materials from Zn-titanate/borosilicate glass of 10/0(ZT10), 9/1(ZT9), 7/3(ZT7) and 5/5(ZT5) ratios were prepared. Their XRD, SEM / EDX, electrical and dielectric properties were investigated. Willemite, rutile and Zn2TiO4 composite materials were developed through the sintering process. The incorporation of glass enhances the formation of willemite. The SEM micrographs show clear euhedral micro-size crystals of Zn2TiO4 spinel and willemite embedded in glassy groundmass. The EDX microanalysis shows the incorporation of Al- element into the structure of the formed phases. Both conductivity (σac) and dielectric constant ( $\upvarepsilon ^{\prime })$ , measured within frequency range 0.2 kHz -1 MHz, and temperature range 298- 573 (K). Glass-free sample showed the highest σac and $\upvarepsilon ^{\prime }$ . Although, 5/5 sample exhibited relative higher values than those with 9/1 and 7/3. The dielectric constant of 9/1 and 7/3 and 5/5 samples show almost an independent behavior over a wide range of temperatures which was attributed to the micro-sized grains of crystalline phases and restraining effect of rigid glassy matrix. The results of ac conductivity may indicate the dominance of electronic conduction over the ionic transfer one in the studied samples. Therefore they may present good candidates for semiconductor materials in electronic devices.