High‐temperature BiFeO₃–PbTiO₃‐Ba(Zr,Ti)O₃ ternary ceramics with excellent piezoelectricity

Abstract

Ternary ceramics of (0.87−x)BiFeO3–xPbTiO3–0.13Ba(Zr0.5Ti0.5)O3 (BF–xPT–0.13BZT, 0.27 ≤ x ≤ 0.37) were prepared by the traditional solid state reaction methods. X‐ray diffraction results display that BF‐xPT‐0.13BZT ternary ceramics of x ≥ 0.29 exhibit the perovskite structure with dominant tetragonal (T) phases mixed with a small amount of rhombohedral (R) phases. Scanning electron microscopy (SEM) images reveal that the average grain size of BF‐xPT‐0.13BZT ternary ceramics is in a range of 10–11 μm, increasing first and then decreasing with the increase of PbTiO3 (PT) content. The low tanδ of about 0.015 and high Curie temperature Tc of above 450°C were obtained for BF‐xPT‐0.13BZT ternary ceramics. Moreover, the fluctuation of piezoelectric coefficient d33 is less than ±10% over a broad temperature range of 30°C–400°C. BF‐xPT‐0.13BZT ternary ceramics for x = 0.33 possess the maximum Tc and d33 of 470°C and 320 pC/N respectively, with the room temperature resistivity of about 1011 Ω·cm. These results indicate that BF‐xPT‐0.13BZT ternary ceramics for x = 0.33 with both excellent piezoelectric properties and high Curie temperature have promising applications in high‐temperature piezoelectric devices.