Sintering time dependent structural and magnetic phase transformations in Pr doped BiFeO3 multiferroics

The structural stability and magnetic properties of Pr doped BiFeO₃ (Bi_0.8Pr_0.2FeO₃) multiferroic ceramics depends on the sintering time. As the sintering time is varied, the structural and magnetic phase transformations has been observed in the multiferroic ceramic. For the present investigation, the samples have been synthesized by conventional solid state reaction method and sintered for 1 h, 2 h and 3 h. The crystal structure of samples has been verified by the Rietveld refinement of XRD patterns. The sample sintered for 1 h is found to possess rhombohedral R3c as major phase. The dominating structural phase changes to orthorhombic Pbam for 3 h sintering. The remanent magnetization in the samples shows a significant increase with the sintering time as observed from M – H loops obtained by VSM. The enhancement in magnetization is suggested to be caused by the increase in canting angle while crossing over from polar rhombohedral R3c phase to antipolar orthorhombic Pbam symmetry.