Enhanced piezoelectric properties of (1-x)[0.675BiFeO₃-0.325BaTiO₃] - xLiTaO₃ ternary system by air-quenching

Lead free (1-x)(0.675BiFeO₃-0.325BaTiO₃)- xLiTaO₃ (BFBTLT, x = 0, 0.01, 0.02, and 0.03, with 0.6 mol% MnO₂ and 0.4 mol% CuO) were prepared by a solid state reaction method, followed by air quenching and their crystalline phase, morphology, dielectric, ferroelectric and piezoelectric properties were explored. An X-ray diffraction study indicates that lithium (Li) and tantalum (Ta) were fully incorporated in the BFBT materials with the absence of any secondary phases. Dense ceramic samples ( > 92 %) with a wide range of grain sizes from 3.70 μm to 1.82 μm were obtained in the selected compositions (0 ≤ x ≤ 0.03) of BFBTLT system. The maximum temperatures (T_max) were mostly higher than 420 °C in the studied composition range. The maximum values of maximum polarization (P_max ≈ 31.01 μC/cm²), remnant polarization (P_rem ≈ 22.82 μC/cm²) and static piezoelectric constant (d₃₃ ≈ 145 pC/N) were obtained at BFBT-0.01LT composition with 0.6 mol% MnO₂ and 0.4 mol% CuO. This study demonstrates that the high T_max and d₃₃ for BFBTLT ceramics are favorable for industrial applications.