Mechanosynthesis and Characterization of Bi1-xGdxFeO3 Multiferroic Materials

Abstract

In the Present work multiferroic materials BiFeO3 were synthesized by high energy ball milling (HEBM) followed by thermal annealing at various temperatures. Further the effect of Gd substitution for Bi was investigated. The concentration of Gd was varied in the range of x=0.0 – 0.20). Phase characterization was carried out by X-ray diffraction. It is found that with increasing Gd content the impurity phase is decreased and single BiFeO3 phase is found at Gd (x = 0.1). Further increase in Gd content from x = 0.1 to 0.2 the impurity phase increases. The room temperature dielectric properties of pure and substituted BiFeO3 were measured in the frequency range from 20 Hz to 1MHz using LCR meter. For all studied samples dielectric constant increased from 110 (x=0.0) to 250 (x=0.10) and then decreases. The dielectric loss found to be more for pure BiFeO3 as compared to Bi1-xGdxO3. The P-E loops are also shows that the maximum polarization is in Bi0.9Gd0.1FeO3 as we increase the percent of Gd in Bi site the polarization becomes decrease. Scanning electron micrograph of Bi1-xGdxFeO¬3 (x=0.0, 0.1, 0.2) sintered sample shows that as we increase the concentration of Gd the grain size decrease. The grain shape is also changed with doping.