Dependence of piezoelectric properties and thermal stability of (1–x)BiFeO3–xBaTiO3 ceramics in relation to accelerometer performance

This study investigates the compositional dependence of piezoelectric and thermal properties in (1– x )BiFeO 3 – x BaTiO 3 ceramics and evaluates their applicability in high-temperature accelerometer applications. Four compositions ( x = 0.25, 0.30, 0.33, 0.35) were synthesized and analyzed for their structural, electrical, and thermal behaviors. The x = 0.25 composition, despite a relatively low piezoelectric coefficient ( ∼ 107 pC/N), exhibited the highest mechanical quality factor ( ∼ 67) and depolarization temperature ( ∼ 450 °C), along with superior resistance to thermally and mechanically induced degradation. When used in compression-mode accelerometers, this composition showed the highest sensitivity (∼23.4 pC/g) and operated up to ∼380 °C. These results suggest that reliable high-temperature sensor performance is influenced not only by the piezoelectric coefficient but also by thermal and mechanical stability, highlighting the importance of comprehensive compositional optimization. Additionally, a strong correlation was observed between the in situ piezoelectric response of the ceramics and the temperature-dependent sensitivity of the assembled sensors. • The composition-dependent piezoelectric and thermal stability of (1– x )BiFeO 3 – x BaTiO 3 ceramics was investigated. • BF-rich ( x = 0.25) composition was found to exhibit the highest Q m and a high depolarization temperature (∼450°C) with excellent thermal stability. • High sensitivity (∼23.4 pC/g) and reliable operation up to ∼380 °C were achieved in an accelerometer based on 0.75BiFeO 3 –0.25BaTiO 3 ceramic. • A strong intrinsic correlation between the in situ d 33 behavior and the temperature-dependent sensor sensitivity was revealed.