Structural Optical and Dielectric Behaviour of Additives Substituted Alumina Zirconia Composite

Abstract

The composite aluminaatzirconia has been proven to be a suitable dielectric material newlinethat can be used in high frequency electronic circuits as insulating material. The newlinecomposite possesses a high dielectric constant with low loss tangent, which may be an newlineappropriate material for sensors and storage devices in electronic industries. As the newlinevariation of dielectric constant with respect to frequency is very less it may be used in newlinefrequency sensors. The high ionic conductivity, low electrical conductivity and chemical newlinestability make aluminaatzirconia composite to behave as an electrolyte in solid oxide newlinefuel cells (SOFCs). Considering all the excellent mechanical, physical, microstructural, newlineoptical, dielectric and electrical properties, aluminaatzirconia composite has been newlinesynthesized by adding different stabilizing agents (Y2O3, MgO) with different amounts newlinethrough the auto-combustion method of synthesis. Here, a constant sintering temperature newline(950and#8451;, 5h) was maintained to get a highly dense microstructure that alternatively newlinecontrols the electrical and dielectric properties of the synthesized composite material. newlineIn our work, first alumina toughened zirconia composite was synthesized. The newlinestructural analysis confirms the formation of a mixed tetragonal alumina and monoclinic newlinezirconia phase by using X-ray diffraction pattern. The FTIR data supports the XRD data newlineby confirming the formation of stretching vibrational modes which can identify the newlinemonoclinic zirconia. The Raman spectroscopy identifies the development of monoclinic newlinezirconia along with also little amount of tetragonal zirconia phase. With an increase in newlinealumina concentration, some extra alumina peaks are also identified. The microstructure newlineanalysis using SEM gives clear information about the formation of a highly fused newlinemicrostructure. To analyse the optical properties and to estimate the band gap energy newlineUV-Visible spectroscopy has been used. A wide band gap that lies within 4 4.5eV has newlinebeen estimated for these composites. The dielectric parameters are estimated b