Magnetic and ferroelectric properties of SmBi4Fe0.5Co0.5Ti3O15 compounds prepared with different synthesis methods

The SmBi4Fe0.5Co0.5Ti3O15 compounds were prepared by the insertion of the SmFe0.5Co0.5O3 into the Bi4Ti3O12 host and the conventional solid state reaction method, respectively. X-ray diffraction analysis indicates that the conventional solid state reaction method favors the formation of a single phase four-layer Aurivillius phase of SmBi4Fe0.5Co0.5Ti3O15 more easily than that prepared by the insertion method. Magnetic and ferroelectric measurements demonstrate that the samples prepared by both methods exhibit coexistence of strong ferromagnetic and weak ferroelectric behaviors at room temperature. Compared with the Bi5FeTi3O15, the ferromagnetism of the SmBi4Fe0.5Co0.5Ti3O15 was dramatically enhanced by the partial substitution of Co for Fe and Sm for Bi. The SmBi4Fe0.5Co0.5Ti3O15 samples exhibit large magnetic responses (2M(r) similar to 643 memu/g and coercive fields 2H(c) similar to 344 Oe) at room temperature.