Structural features, dielectric behaviour of spinel type magnesium aluminate synthesized by the auto-combustion method

Abstract

Abstract In the present work, the auto-combustion route was used to synthesized the spinel type magnesium aluminate (MgAl2O4). The structural, dielectric, and electrical properties of the sample have been characterized by using X-ray diffraction, FTIR and dielectric spectroscopy. The X-ray diffraction pattern reveals that the prepared compound has a single-phase cubic spinel structure with space group Fd3m. The crystallite size (D) of the prepared sample was found to be 28.87 nm. The dielectric behaviour of the sample and ac conductivity have been examined in the frequency range of 102 Hz to 105 Hz at different temperatures. It was observed that the dielectric constant and dielectric loss decreases with increasing value of applied frequency due to ceasing effect of polarization and attains a saturated value at a higher frequency range. The ac conductivity shows an increasing nature with frequency followed by charge carrier hopping mechanism.