Synthesis and Magnetic Properties of BiFeO3, (BiFeO3)0.95(BaTiO3)0.05, and (Bi0.95Ba0.05)(Fe0.95Ti0.05)O3 Ceramics

Magnetization, grain size, structure, and temperature-dependent dielectric permittivity of BiFeO3 (BFO) (BiFeO3)(0.95)-(BaTiO3)0.05(5%BTO-BFO), and (Bi0.95Ba0.05)(Fe0.95Ti0.05)O-3 [5%(Ba, Ti)-BFO] ceramics have been carried out. BFO and 5% BTO-BFO exhibit an typical antiferromagnetic behavior, whose magnetization curve is linear with magnetic field at room temperature. The magnetic hysteresis loop of 5%(Ba, Ti)-BFO ceramic shows a weak ferromagnetic behavior with a small remanent magnetization of about 0.01 emu/g possibly due to a higher density in the grain matrix. This result also implies that the A-and B-site substitutions with Ba2+ and Ti4+ could efficiently suppress the spiral magnetic modulation. The magnetic susceptibilities of BFO, 5% BTO-BFO, and 5%(Ba, Ti)-BFO ceramics are about 1.9 x 10(-5), 5.43 x 10(-6), and 8.67 x 10(-6) emu/ gOe, respectively. Frequency-dependent dielectric maxima were observed in BFO, 5% BTO-BFO, and 5%(Ba, Ti)-BFO ceramics upon heating. This dielectric response is likely triggered by the antiferromagnetic-paramagnetic transition near the Neel temperature.