BZT substitution effect on the characteristics of (1-x) MT – x BZT composite ceramics synthesized by the sol–gel method

Abstract

This paper addresses a crucial gap in the effect of adding BaZr0.1Ti0.9O3 (BZT) on the structural, microstructural, dielectric, and electrical properties of MgTiO3 (MT) material. These ceramics with the chemical composition (1-x) MT – x BZT were synthesized with different compositions ranging from × = 0.0 to 1.0 with a 0.1 step using the sol–gel reaction process. The X-ray diffraction (XRD) results and Rietveld refinement analysis showed the formation of a tetragonal phase with the P4mm space group for the BZT sample and a hexagonal phase with the R-3 space group for MT ceramics, without any secondary phases. However, (1-x) MT – x BZT composites with × ranging from × = 0.1 to 0.9, showed a coexistence of tetragonal (P4mm) and hexagonal (R-3) phases. Scanning Electron Microscopy (SEM) was used to investigate the morphology and grain size of the compounds. The SEM results revealed a clear decrease in grain growth for x = 0.6 of BZT content with the higher density. Furthermore, the dielectric properties of these composites were studied by impedance spectroscopy, which showed a single diffuse dielectric phase transition for all the BZT-MT composites. There was a clear increase in dielectric permittivity (εr′) value with the increase of the BZT content. This broad phase transition is highly desired and has not been observed in previous studies. The obtained composite ceramics could open the way to lead new applications in microelectronic devices.

Keywords

• Ceramic
• BZT-MT
• Sol–gel
• X-ray diffraction
• Dielectric properties
• Phase transition