Dielectric and piezoelectric properties of Bi1/2Na1/2TiO3–SrTiO3 lead–free ceramics

Large Electric Field-Induced Strain Response Under a Low Electric Field in Lead-Free Bi1/2Na1/2TiO3-SrTiO3-BiAlO3 Ternary Piezoelectric Ceramics

“…* value at the relatively low electric field of 3 kV/mm, which is superior to other reported BNT-based materials and comparable to other lead-free ferroelectric/relaxor composites. 16,23,24,26,29,[33][34][35] As we discussed earlier, we assume that this excellent d 33 * value at low driving field for BNT-ST-2BA ceramics originates from the coexistence of NER and ER (more precisely, it seems that nonergodicities are locally spread in the ergodic relaxor).…”

“…It has been reported that (1-x)BNT-xSrTiO 3 ceramics undergo a phase transition from a nonergodic relaxor (NER) to an ER for x 0.26 with a large strain of about 0.25% under 4 kV/mm. [29][30][31] It has been suggested that the naturally formed core-shell structure (core and shell regions are comprised of ferroelectrics and relaxor, respectively) in BNT-ST ceramics is responsible for these improved strain properties. [30][31][32] Accordingly, it is noted that intentionally or naturally induced ferroelectricities (or nonergodicities) in BNT-based incipient piezoceramics play an important role for improving electromechanical strain properties with a low operating field.…”

Clarification on phase transition behaviors by local strain engineering in Bi1/2Na1/2TiO3–SrTiO3‐based ternary ceramics

“…Although the crystallographical identity for BNT–ST ceramics is still a controversial issue, it has been known that the solid solution BNT–ST ceramics forms a morphotropic phase boundary (MPB) consisting of a rhombohedral and a pseudocubic at 25–28 mol% of ST content. Furthermore, it was reported that a large normalized strain ( S max / E max ) of about 600 pm/V under a relatively low field (4 kV/mm) was obtained in BNT–ST ceramics of MPB regions 16–19 . This abnormally large strain in BNT‐based (or BNT–ST) ceramics is associated with the reversible electric‐field‐induced phase transition from an ergodic relaxor (ER) to a ferroelectric (FE) 20–24 .…”

“…Furthermore, it was reported that a large normalized strain (S max /E max ) of about 600 pm/V under a relatively low field (4 kV/mm) was obtained in BNT-ST ceramics of MPB regions. [16][17][18][19] This abnormally large strain in BNT-based (or BNT-ST) ceramics is associated with the reversible electric-field-induced phase transition from an ergodic relaxor (ER) to a ferroelectric (FE). [20][21][22][23][24] Recently, several studies have suggested that exploring ternary systems can result in discovering a high-performance piezoelectric in BNT-ST ceramics.…”

Structural, Ferroelectric, Pyroelectric, and Dielectric Study of Bi0.5Na0.5TiO3 Ceramics synthesized with Precursors Obtained by Sol-Gel Method doped with Lanthanum

“…Notwithstanding the above, the BNT has been widely studied as a modified system through use of BNT-based solid solutions in order to improve its properties with another systems such as BaTiO3 (BT) (from d33=83pC/N, kp=15.9% for pure BNT system to d33=155pC/N, kp=36.7% for 0.4BNT-0.06BT) [9], SrTiO3 (ST) (piezoelectric improvement until d33* ≈ 620 pC/N for 0.72BNT-0.28ST) [10], K0.5Na0.5TiO3 (KNN) (piezoelectric improvement until d33=94 pC/N and kp≈27% for 0.94BNT-0.06KNN [11], and Bi0.5K0.5TiO3 BKT (piezoelectric and dielectric improvement until d33=115 pC/N and r=1660 for 0.82BNT-0.18BKT) [12].…”