Influence of different synthesizing steps on the multiferroic properties of Bi5Fe1Ti3O15 and Bi5Fe0.5Co0.5Ti3O15 ceramics

The compounds Bi5FeTi3O15 (BFTO) and Bi5Fe0.5Co0.5Ti3O15 (BFCT) were prepared by incorporating BiFeO3 (BFO) and BiFe0.5Co0.5O3 (BFCO) into the host Bi4Ti3O12 (abbreviated as BFTO-1 and BFCT-1) and by the conventional solid-state reaction method (abbreviated as BFTO-2 and BFCT-2). X-ray analysis indicates a four-layer Aurivillius phases with an orthorhombic symmetry. At room temperature, the remnant polarization (2P (r)) of BFTO-1, BFTO-2, BFCT-1, and BFCT-2 samples are measured to be 11.0, 3.5, 13, and 6.3 mu C/cm(2), respectively, and the corresponding remnant magnetization (2M (r)) are about 2.72 x 10(-3) memu/g, 1.51 x 10(-3) memu/g, 7.6 and 2.1 memu/g, respectively. Both BFTO-1 and BFCT-1 samples exhibit the dielectric peaks at around 755 and 772 A degrees C in their epsilon-T curves, respectively.