Structural transition, electrical and magnetic properties of Cr doped Bi0.9Sm0.1FeO3 multiferroics

The structural, vibrational, electrical and magnetic properties of Bi0.9Sm0.1Fe1-xCrxO3 (0.02 ≤ x ≤ 0.1) ceramics have been investigated in the vicinity of the morphotropic phase boundary (MPB) between the rhombohedral and orthorhombic structures. X-ray diffraction (XRD) patterns reveal a gradual formation of the orthorhombic phase and Bi14CrO24 impurity with increasing chromium concentration. The Rietveld refinement and Raman scattering analysis confirm the structural transformation from the polar R3c to the anti-polar Pnam phases. The Cole-Cole plots show two relaxation regimes which are attributed to gain and grain boundary responses above room temperature. The slim magnetic hysteresis loops are observed in samples with x = 0.02–0.08, while a robust loop with the coercivity field of Hc ≈ 1200 Oe is observed for x = 0.1 sample where the canted antiferromagnetic phase is significantly contributed to the total magnetization. This result approves that the cycloidal spin structure cannot be suppressed by Cr doping. •Cr doped Bi0.9Sm0.1FeO3 samples were synthesized by solid-state reaction method.•The structural analysis reveals a coexistence of the polar R3c rhombohedral and antipolar PbZrO3-type structures.•Cr doping cannot suppress the cycloidal spin structure in the R3c phase.•The enhanced magnetization is attributed to an increase in PbZrO3-type phase percentage.