Structural, magnetic and dielectric properties of Bi1−ySryFe(1−y)(1−x)Sc(1−y)xTiyO3 (x = 0–0.2, y = 0.1–0.3) ceramics

In this study, bulk ceramics with general formula Bi1−ySryFe(1−y)(1−x)Sc(1−y)xTiyO3 (x = 0–0.2, y = 0.1–0.3 mol%) were prepared by traditional solid-state reaction method. As a comparison, bulk BiFeO3 (BF) was also sintered by rapid sintering method. Their structural, magnetic, dielectric properties were investigated. X-ray diffraction analysis indicated that apart from a small amount of secondary phase detected in BF, all other samples crystallized in pure perovskite structure and maintained original R3c space group. The room temperature M–H curves were obtained. While BF had a coercive magnetic field (Hc) of 150 Oe, Bi1−ySryFe1−yTiyO3 solid solutions had a much larger value (for y = 0.1, 0.2, 0.3, Hc were 4537, 5230 and 3578 Oe, respectively). Sc3+ substitution decreased the Hc values of these solid solutions remarkably, and resulted in soft magnetic properties, as well as a decrease of the dielectric loss. At 1 MHz, the tan δ of Bi0.7Sr0.3Fe0.7(1−x)Sc0.7xTi0.3O3 with x = 0.05, 0.1, 0.15, 0.2 were 0.1545, 0.1078, 0.1046 and 0.1701, respectively.

Bi1−ySryFe(1−y)(1−x)Sc(1−y)xTiyO3 (x = 0–0.2, y = 0.1–0.3) ceramics were obtained by solid-state reaction method. Addition of scandium could simultaneously reduce magnetic coercive field and enhance dielectric properties of prepared samples.Figure optionsDownload as PowerPoint slideResearch highlights▶ The electrical resistivity of BiFeO3 is enhanced by forming solid solution with SrTiO3. ▶ We further replace Fe3+ by Sc3+ in solid solution to reduce Hc and achieve a soft magnet. ▶ Structure–magnetic property relationship has been established by Rietveld refinement. ▶ Sc3+ substitution can inhibit the dielectric loss effectively.