Saji S K; R Radhakrishnan; T Jeyasingh; R Vinodkumar; Shibu M. Eappen; P R Sobhana Wariar
Abstract
perovskite material was prepared by solution combustion technique. XRD results revealed that the material crystallizes in a rhombohedral crystal symmetry with space group Rc. The ac conductivity and dielectric properties of the sintered pellet of the sample have been investigated in the frequency ...
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perovskite material was prepared by solution combustion technique. XRD results revealed that the material crystallizes in a rhombohedral crystal symmetry with space group Rc. The ac conductivity and dielectric properties of the sintered pellet of the sample have been investigated in the frequency range 1Hz to 1MHz for a wide range of temperatures. The experimental results indicate that the ac conductivity (ω), dielectric constant () and dielectric loss ( ) depends on depends on the temperature and frequency. The ac conductivity was found to obey the power law with and the behavior of exponent n with temperature and the value of n suggest ion hopping is the charge transport mechanism in the material. The obtained results are compared to the principal theories that describe the universal dielectric response behavior. The value and were found to be temperature and frequency dependent. Copyright © 2018 VBRI Press.
Anju .; Ashish Agarwal; Praveen Aghamkar
Abstract
Barium substituted bismuth ferrite (Bi0.8Ba0.2FeO3) was synthesized using ethylene glycol based sol-gel method followed by heat treatment at 800°C for 15 min. In order to study the effect of barium substitution on structural parameters the rietveld refinement of the sample was performed. Structural ...
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Barium substituted bismuth ferrite (Bi0.8Ba0.2FeO3) was synthesized using ethylene glycol based sol-gel method followed by heat treatment at 800°C for 15 min. In order to study the effect of barium substitution on structural parameters the rietveld refinement of the sample was performed. Structural transition from the rhombohedral perovskite (ABO3) crystal structure to pseudo-cubic has been confirmed. Ba substitution at Bi site suppresses the secondary phases of BiFeO3 such as Bi2Fe4O9, Bi25FeO39 etc. The crystallite size of the prepared barium substituted BiFeO3 (BBFO) nano-multiferroic calcined at 800°C is found to be ~ 20 nm. The functional groups in the calcined sample were identified by FTIR analysis. TG-DSC analysis of the sample has also been performed. It is expected that structural changes made by barium in BiFeO3 would also affect its magnetic behavior. Copyright © 2017 VBRI Press.
