Undoped and Mn-doped (1−
x)BaTiO
3–
xBi(Ni
1/2Ti
1/2)O
3 (
x = 0.03–0.7) ceramics were synthesized by a conventional solid state route. X-ray diffraction patterns revealed that the crystal structure was a tetragonal perovskite at
x = 0.03, a pseudo-cubic perovskite at
x = 0.1 and 0.3, and mixed phases at
x = 0.5–0.7. The dielectric and piezoelectric responses were ferroelectric at
x = 0.03 and relaxor-like at
x = 0.1–0.7. The polarization–electric field and strain–electric field responses were suppressed at the relaxor compositions, and the large-field piezoelectric constant was 25–40 pm/V at
x = 0.3–0.7. As
x increased, the temperature of the maximum dielectric constant decreased compared to the Curie temperature of BaTiO
3 at
x ≤ 0.1, and then it increased and reached 325°C at
x = 0.7. At
x = 0.3–0.7, the dielectric constant was less temperature dependent. These results suggest that the samples may be suitable for high temperature capacitor application.
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