Effect of B-site W/Mn co-doped on the structural and electrical properties of CaBi2Nb2O9

• Published in: Journal of materials science. Materials in electronics 2023-11, Vol.34 (31), p.2070, Article 2070
• Main Authors: Huang, Mingying, Jiang, Xiangping, Chen, Chao, Nie, Xin, Huang, Xiaokun, Huang, Shaohua, Chen, Chaoqun, Zhao, Chong, Yan, Sixuan
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Curie temperature; Dielectric loss; Doping; Electric properties; Electrical properties; Ferroelectricity; High temperature; Lead free; Materials Science; Optical and Electronic Materials; Piezoelectric ceramics; Polarization; Thermal stability
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-023-11454-y

In this study, we employed the conventional solid-state reaction method to prepare high Curie temperature ( T c ) lead-free piezoelectric ceramics by co-doping W 6+ and Mn 2+ into CaBi 2 Nb 2− x (W 3/4 Mn 1/4 ) x O 9 (designated as CBNWM- x , with 0 ≤  x  ≤ 0.08), and our focus was to enhance the electric properties, while maintaining a high T c . The co-doping of W 6+ and Mn 2+ into CBN ceramics yields improved DC resistivity ( ρ DC ) and reduced dielectric losses, and leads to a significant enhancement in piezoelectric activity and ferroelectric polarization. In particular, CaBi 2 Nb 1.94 (W 3/4 Mn 1/4 ) 0.06 O 9 is highlighted as the most promising composition, exhibiting remarkable electric properties including a d 33 value of 15.2 pC/N, a high T c of 916.1 °C, a low dielectric loss (tan δ ) of 2.7% (at 500 °C), a ρ DC value of 8.47 × 10 6 Ω cm (at 450 °C), and a remanent polarization ( P r ) of 11.0 µC/cm 2 . Notably, even after annealing at 900 °C for 30 min, the d 33 value remains at 14 pC/N. The great performance improvement and good thermal stability show that CBN ceramics have promising applications in the field of high-temperature piezoelectric devices.