Multiferroism and magnetoelectric coupling in single-phase Yb and X (X=Nb, Mn, Mo) co-doped BiFeO3 ceramics

A series of Yb and X co-doped BiFeO3 (X=Nb, Mn, Mo) and undoped BiFeO3 polycrystalline ceramics were prepared by sol-gel method. The X-ray diffraction pattern confirmed the rhombohedral perovskite structure for all the ceramics. Reitveld refinement results bring out the impact of doping on the structural distortion. The Transmission Electron Micrograph observation reveals the nanostructure of the doped samples. Well saturated ferromagnetic hysteresis curves were obtained for the doped samples in contrary to undoped BiFeO3 and this is attributed to the distortion of spin spiral structure. The doped ceramics exhibited improved ferroelectric parameters and very low leakage current density of the order of 10(-9) to 10(-7)A/cm(2), which is remarkably lower than that of undoped BFO. Remarkable dielectric properties were exhibited for the doped samples. An abrupt noticeable enhancement of magetoelectric coupling for the doped samples in comparison with the undoped BiFeO3 has been demonstrated in our work. The left figure depicts the ferromagnetic character and the right figure depicts the ferroelectric behavior of (Yb, Nb), (Yb, Mn) and (Yb, Mo) doped BiFeO3 multiferroic [GRAPHICS] HighlightsNovel (Yb, X) doped BFO (X=Nb, Mn, Mo) multiferroic materials were synthesized.All the doped samples exhibit significantly enhanced magnetic, ferroelectric and dielectric properties.Leakage current of the doped BFO is very low compared to that of undoped BFO.Remarkably improved magnetoelectric coupling is shown by the doped samples.