Synthesis, Structural, Electrical and Thermal Properties of ScFeO 3 Ceramic

Abstract

The ceramic sample of ScFeO3 (SFO) has been prepared by standard high temperature solid state reaction method using high purity oxides. The formation of the compound as well as structural analysis has been carried out by X-ray diffraction method which confirmed the rhombohedral symmetry with polar space group R3c. The average grain size obtained by the Scherrer formula is of the order of 560 A. The surface morphology of SFO has been investigated by Atomic Force Microscopy (AFM). The average roughness obtained by two dimensional surface morphology ranges from 5.80 nm to 20.2 nm for surface area 5×5μm2 to 10×10μm2 respectively. The dielectric constant and dielectric loss as a function of frequency (100Hz-1MHz) and temperature (RT-650K) have been measured. At RT and 1kHz frequency the material shows high dielectric constant value (around 1800) with lossy nature. The transport properties such as I-V characteristics, ac and dc conductivities have been measured and activation energy was calculated using the Arrhenius relation. The I-V characteristic along with ac and dc conductivity studies show semiconducting behaviour with dc activation energy of 0.81eV. The Magnetic measurement indicates weak ferromagnetic behaviour. The Enthalpy change (ΔH), Specific heat (Cp) and % Weight-loss of the compound have been measured using DTA/TGA technique. The DTA curve shows transition around 1088K with Cp =2.3Jg-1K-1 and ΔH=18.4Jg-1. The low weight loss (around 2%) from RT -1200K suggest that the material is thermally stable. The results are discussed in detail.