Synthesis and electromechanical properties of LiTaO₃-modified BiFeO₃–BaTiO₃ piezoceramics

In this work, lead-free MnO₂ (0.6 mol%) and CuO (0.4 mol%) mixed (1–x)(0.675BiFeO₃ – 0.325BaTiO₃) – xLiTaO₃ (BF–BT–xLT+MC, with x = 0–2 mol%) ceramics were fabricated by a conventional solid-state reaction followed by quenching process. The crystal structure and microstructure of the BF–BT–xLT+MC ceramics were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. Enhancement in dielectric, ferroelectric and field-induced strain properties were observed at optimum amount of LT addition in BF–BT+MC ceramics. The ferroelectric loops shows significant enhancement in polarization response for 1 mol% LT-modified in BF–BT+MC composition. In addition, for the same composition a substantial improvement (70%) in comparison with the pure BF–BT ceramics was realized in the dynamic piezoelectric coefficient (d^*₃₃ = S_max/E_max).