Structural and Electrical Characteristics of an Aurivillius Family Compound Bi2LaTiVO9

• Published in: Crystal research and technology (1979) Vol. 53; no. 12
• Main Authors: Gupta, Prabhasini, Mahapatra, Prasanta Kumar, Choudhary, Ram Naresh Prasad
• Format: Journal Article
• Language: English
• Published: 01.12.2018
• Subjects: Cole–Cole plot; correlated barrier hopping model; ferroelectric; non‐Debye relaxation; X‐ray diffraction
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/crat.201800045

The synthesis and characterization of bismuth lanthanum titanium vanadate (i.e., Bi2LaTiVO9), a new member of bismuth layer structure ferroelectric, are reported in this paper. The compound crystallizes in a single phase orthorhombic system. The smallest pentavalent V5+ ion in the compound results in higher polarization and low loss properties as compared to other similar compounds of Aurivillius family. The partial substitution of La3+ ion at the Bi3+ sites of Bi2O2 layers results in relaxor ferroelectric behavior with an expected decrease in transition temperature. The activation energy for both relaxation and conduction processes is in the vicinity of the activation energy of oxygen vacancy suggesting oxygen–vacancy activated charge carriers in both conductivity and relaxation processes. Bi2LaTiVO9, synthesized by a mixed‐oxide route at 850 °C, crystallizes in the orthorhombic crystal system. Addition of V5+ ion at the center of the octahedra provides relatively high dielectric constant and low tangent in the high‐frequency range. The ferroelectric relaxor characteristics and the decrement in transition temperature are due to the partial occupancy of La3+ for Bi3+ in Bi2O2 layer.