| Summary: | BiGaO<sub>3</sub> doped BiFeO<sub>3</sub>–BaTiO<sub>3</sub> ceramics were prepared by the traditional solid-phase synthesis process. The phase analysis, microstructure, piezoelectric, ferroelectric, dielectric properties, and thermal stability of 0.7BiFeO<sub>3</sub>-(0.3 − <i>x</i>)BaTiO<sub>3</sub>-<i>x</i>BiGaO<sub>3</sub> (Abbreviated as BF–BT-<i>x</i>BG) were investigated. The results show that the ceramics have rhombohedral (<i>R</i>) and tetragonal (<i>T</i>) structures. Particle dimensions gradually get bigger with the increase of BiGaO<sub>3</sub> concentration, and dense ceramic grains were observed through SEM. Electrical properties of BF–BT-<i>x</i>BG are improved after adding a small amount of BiGaO<sub>3</sub>: piezoelectric constants <i>d</i><sub>33</sub> = 141 pC/N, electromechanical coupling coefficient <i>k</i><sub>p</sub> = 0.314, mechanical Quality Factor <i>Q</i><sub>m</sub> = 56.813, dielectric loss tanδ = 0.048, residual polarization intensity <i>P</i><sub>r</sub> = 18.3 µC/cm<sup>2</sup>, Curie temperature <i>T</i><sub>c</sub> = 485.2 °C, depolarization temperature <i>T</i><sub>d</sub> = 465 °C for <i>x</i> = 0.003. The “temperature-piezoelectric performance” curve under in situ <i>d</i><sub>33</sub> indicates that piezoelectric properties <i>d</i><sub>33</sub> increase rapidly with increasing temperature. Remarkably, the piezoelectric response <i>d</i><sub>33</sub> reaches a maximum of 466 pC/N at a temperature <i>T</i> = 340 °C, and afterward, reduces gradually to zero with increasing temperature until 450 °C.
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