Analysis of dielectric and electrical transport properties of NdFeAsO ceramic

Abstract

Abstract The iron-based ceramic NdFeAsO was synthesized by the solid-state reaction method. The tetragonal crystal structure was confirmed at room temperature through the X-ray diffraction technique. The dielectric characteristics i.e. dielectric constant (εr) and loss tangent (tanδ) of the sample were studied at a wide range of temperature and frequencies with an impedance analyzer and revealed that these quantities decreased with an increase in frequency. The dielectric anomalies were observed in the studied sample, which was found to be shifting towards the higher temperature side on increasing the frequency. The analysis of ac conductivity data of the compound obeyed Jonscher’s universal power law as well as the Arrhenius equation. The compound showed a negative temperature coefficient of resistance (NTCR) behavior. The electrical conduction mechanism in the sample can be explained through the correlated barrier hopping (CBH) model.

Keywords

• X-ray diffraction
• ceramic materials
• dielectric properties
• conductivity
• density of states