Effect of Y3+ substitution on structural, electrical and optical properties of BiFeO3 ceramics

Bi1−xYxFeO3 ceramics with compositions x=0.00, 0.05, 0.10, 0.15 and 0.20 were synthesized by the solid state reaction route. All the compositions have shown single phase formation with minor impurities. Microstructural studies reveal that Y3+ substitution influences grain growth, which in turn affects the dielectric and optical properties of these materials. Dielectric anomalies in temperature dependent dielectric plots at around the magnetic transition temperature (TN) indicate magneto-electric coupling. Ac conductivity has been found to decrease with increasing Y3+ concentration. FTIR spectra show two broad absorption bands due to the overlapping of Fe-O and Bi-O group′s vibrations in the region 400–700 cm−1. The photoluminescence spectra of these ceramics exhibit band edge emission at 458 nm (2.67 eV) in blue region. The emission in green region may be attributed to the transitions related to the defects and Y3+ ions.