Study on dielectric and ferroelectric properties of NBT-based lead-free piezoelectrics doped by Sb2O3

The NBT piezoelectric ceramics with drop BiSbO3 (x = 0, 0.01, 0.02, 0.03) were prepared by the conventional ceramic technique. Dielectric and ferroelectric properties of series samples were discussed systematically. From XRD results, it was found a formation of single phase of perovskite structure in series samples. Scanning electron microscope (SEM) micrographs of the natural surface of samples indicated that the compact structure was obtained. With the increase content of BiSbO3, the dielectric constant of the samples decreased remarkably, the relaxation characters of samples were enhanced, while the dissipation factors kept stable, which attributed to more disorder of A and B sites in the lattice structure. The results showed that the introduction of BiSbO3 into NBT-based ceramics has reduced the coercive force remarkably from 7.3 kV/mm to 4 kV/mm, maintaining the large saturation polarization, which meant that the problem of high coercive field could be solved efficiently.