Structural and electrical properties of La-modified BiFeO3–BaTiO3 composites

• Published in: Journal of materials science. Materials in electronics Vol. 25; no. 5; pp. 2086 - 2095
• Main Authors: Behera, C., Choudhary, R. N. P., Das, Piyush R.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.05.2014; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Optical and Electronic Materials; BiFeO3; Bulk Resistance; BaTiO3; High Frequency Side; Complex Impedance
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-014-1844-z

In the present investigation, La-modified solid solutions of BiFeO 3 (BFO) and BaTiO 3 (BT) in different molar ratios [i.e., (Bi 0.5− x La x Ba 0.5 )(Fe 0.5 Ti 0.5 )O 3 , with x  = 0.0, 0.05, 0.10 and 0.15)] have been synthesized using a solid-state reaction route. Structural and electrical properties of single phase (with minor secondary phase) of BFO–BT system have been studied in details to understand their ferroelectric and other properties. Preliminary X-ray diffraction analysis confirms the formation of a new system, which is different from that of its parent compounds. Substitution of a small amount BaTiO 3 into BiFeO 3 enhances dielectric and ferroelectric responses and reduces electrical leakage or tangent loss. The ac conductivity obeys Jonscher’s universal power law. The electrical behavior of the samples was investigated by impedance spectroscopy in a wide temperature range (25–525 °C) at different frequency (1 kHz–1 MHz). The impedance spectroscopy of the materials also confirms the origin of the relaxation mechanism in the system.