Structural and electrical characterization of BiFeO3–NaTaO3 multiferroic
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Using a standard high-temperature solid-state reaction technique, polycrystalline samples of (Bi1−x , Na x ) (Fe1−x , Ta x ) O3 (x = 0.0, 0.5) were prepared. The formation of the desired materials was confirmed by X-ray diffraction. The surface texture of the prepared materials recorded by scanning electron microscope exhibits a uniform grain distribution with small voids suggesting the formation of high-density pellet samples. The impedance and dielectric properties of the materials were investigated as a function of temperature and frequency. The relative dielectric constant and loss tangent of BiFeO3 decrease on addition of NaTaO3 (x = 0.5). The effect of addition of NaTaO3 on grain and grain boundary contributions in the resistive and capacitive components of BiFeO3 was studied using complex impedance spectroscopy. The value of activation energy due to both grain and grain boundary of both the samples is nearly same. The nature of variation of dc conductivity confirms the Arrhenius behavior of the materials. Study of frequency dependence of ac conductivity suggests that the materials obey Jonscher’s universal power law and the presence of ionic conductivity.
KeywordsBiFeO3 Complex Impedance Constant Phase Element Mobile Charge Carrier Ferroelectric Phase Transition
Authors are thankful to Ms Samita Pattnayak for providing SEM image for pure BFO.
- 9.N.A. Hill, J. Phys. Chem. B 104, 6694 (2000)Google Scholar
- 18.E.Wu, POWD: an Interactive Power Diffraction Data Interpretation And Indexing Program V21 School of Physical Sciences (Flinder University of South Australia, Bedford Park)Google Scholar
- 25.S. Selvasekarapandian, M. Vijaykumar, Mater. Chem. Phys. 80, 29 (2003)Google Scholar
- 37.J.R. Macdonaled, Impedance Spectroscopy, Emphasizing Solid Materials and Systems (Wiley, New York, 1987)Google Scholar