Enhanced electrical properties of lead-free Bi4−xSbxTi3O12 ceramics with high Tc

• Phase structure changed with increasing Sb content.
• The intensities of the lattice vibration modes decrease.
• Bands and bandwidths in all frequency demonstrate changes.
• Sb3+ into the Bi4Ti3O12 (BIT) matrix had the effect of increasing the material grain size.
• εr, εm, Pr, d33 and Tc of Bi3.90Sb0.10Ti3O12 are found to be 307, 3492, 8.09 μC cm−2, 18 pC/N and 660 °C, respectively.

Bi4−xSbxTi3O12 (BST) ceramics were prepared and studied in this work in terms of Sb3+-modified microstructure and phase development as well as electrical response. By increasing Sb content, the phase structure of the ceramics changed from orthorhombic (Bi4Ti3O12-like) to pyrochlore (Bi2Ti2O7-like) phase. Raman spectroscopy showed that the intensities of the lattice vibration modes at frequencies decrease, whereas all bands and bandwidths in all frequency numbers also demonstrate changes. According to the results processed from SEM, Sb3+ into the Bi4Ti3O12 (BIT) matrix had the effect of increasing the material grain size. εr, εm, Pr, d33 and Tc of Bi3.90Sb0.10Ti3O12 ceramics are found to be 307, 3492, 8.09 μC cm−2, 18 pC/N and 660 °C, respectively. And Bi4−xSbxTi3O12 ceramics have good temperature stability, which is very suitable for the practical high-temperature applications.