ABSTRACT
Bismuth layer-structured ferroelectric (BLSF) compound barium bismuth niobate (BBN) with a chemical formula BaBi2Nb2O9 has been prepared using a solid-state reaction technique. Preliminary structural and microstructural properties of the compound were investigated through X-ray diffraction technique and SEM-microphotographs respectively. Its dielectric properties have been analyzed within a wide range of temperature and frequency. Relative dielectric constant (εr) of the material is found to be higher at a lower frequency suggesting a normal behavior of ferroelectrics. Studies of temperature–frequency dependence of dielectric studies show broadened anomaly (with shift in peak) suggesting the occurrence of diffused-relaxor type of ferroelectric phase transition well above the room temperature. Temperature dependence of the ac-conductivity at selected frequencies and the values of activation energies in the different regions suggest that the conduction process in the material is mainly due to singly ionized oxygen vacancies in the ferroelectric region.
