Investigation of Structural, Electrical and Vibrational Properties of Bi1.98A0.02Fe4O9 (A= Ba, Ce) Multiferroic Ceramics

In this paper, we report the synthesis, phase formation and basic characterization of polycrystalline Bi 2 Fe 4 O 9 , Bi 1.98 Ba 0.02 Fe 4 O 9 , and Bi 1.98 Ce 0.02 Fe 4 O 9 sample prepared through sol-gel route. Crystal structure of the as prepared samples have been characterized by X-ray diffraction and Raman scattering spectroscopy. All the obtained XRD peaks could be indexed to orthorhombic Pbam structure and revealed the formation of Bi 2 Fe 4 O 9 . Raman spectrum identifies A g , B 2g and B 3g active optical phonon modes. The size and morphology of the nanoparticles have been analyzed using scanning electron microscopy (SEM). Dielectric constant (e') decreases with increase in frequency and it is constant at higher frequencies region and it can be explained on the basis of ionic conduction phenomenon in the low frequency region. The value of e' for all Bi 2 Fe 4 O 9 based S1, S2, S3 and S4 samples are about 37, 75, 40 and 393, respectively at frequency 10 Hz. The observed properties signify that these materials are very useful in advanced technological and practical applications.