Dielectric and impedance spectroscopy of aluminium oxide substituted fused silica samples

Abstract

This paper shows a comparative study of sintered and thermally quenched Al2O3 substituted fused silica ceramics processed by colloidal suspension route. The structural analysis is performed using X-ray diffraction measurements. The natural surface micrographs present close packing of non-uniform shape of grains. The high permittivity and low loss are illustrated from frequency dependent permittivity. The impedance spectroscopy shows non-Debye type relaxation mechanism. The Nyquist plot shows the presence of only grain effect. The overlapping large Polaron tunnelling model is attributed from the conduction studies of both sintered and quenched samples. © 2019, Springer Nature Switzerland AG.