Ca2+ doping effects on the structural and electrical properties of Na0.5Bi4.5Ti4O15 piezoceramics. Issue 21 (1st November 2022)

• Record Type: Journal Article
• Authors: Zhang, Yanyan; Ke, Xucheng; Zhao, Kunyu; Zhou, Zhiyong; Liang, Ruihong
• Is Part Of: Ceramics international. Volume 48:Issue 21(2022)
• Page Start: 31265
• Page End: 31272
• Publication Date: 2022-11-01
• Subjects: BLSFs -- Na0.5Bi4.5Ti4O15 -- Piezoelectric coefficient -- Thermal annealing; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.06.201
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Bismuth layer structured Na0.5 Bi4.5 Ti4 O15 (NBT) ferroelectric is one of the most promising materials for potential applications at high temperature. However, it is challenged to achieve a balance between high Curie temperature piezoelectric coefficient and excellent thermal stability for NBT piezoceramics. Here, through chemical modification at the A site of NBT with Ca 2+, novel (Na0.5 Bi0.5 )1-x Cax Bi4 Ti4 O15 piezoceramics with excellent properties fabricated by solid state reaction were studied. After doping of Ca 2+, the Curie temperature T C increased from 648 °C to 662 °C while the piezoelectric coefficient d 33 increased from 14 pC/N to 22 pC/N which can be attributed to the intrinsic contribution of TiO6 octahedral lattice distortion (tilting and rotation) and the extrinsic contribution of the increased density of domain walls. The composition of (Na0.5 Bi0.5 )0.95 Ca0.05 Bi4 Ti4 O15 ceramics with x = 0.05 has the optimal performance with high T C of 655 °C, large d 33 of 22 pC/N, high electrical resistivity ρ close to 10 7 Ω cm at 500 °C and especially excellent thermal stability of d 33 only about 5% reduction after being annealed at 625 °C. The work effectively reveals the great potential of CNBT-5 ceramics for high-temperature piezoelectric applications.