Thermally-Stable High EFIS Properties of Ternary Lead-Free BNT-BKT-BZ Piezoelectric Ceramics

• Published in: Journal of electronic materials 2023-05, Vol.52 (5), p.2977-2985
• Main Authors: Dinh, Thi Hinh, Han, Hyoung-Su, Tran, Vu Diem Ngoc, Le Van, Vinh, Lee, Jae-Shin
• Format: Article
• Language: English
• Subjects: Barium zirconates; Bismuth titanate; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Diffraction patterns; Electric fields; Electronics and Microelectronics; Ferroelectricity; Induced polarization; Instrumentation; Lead free; Materials Science; Optical and Electronic Materials; Original Research Article; Perovskite structure; Perovskites; Phase transitions; Piezoelectric actuators; Piezoelectric ceramics; Piezoelectricity; Sintering; Solid State Physics; Specific gravity; Thermal stability
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-023-10263-7

Ternary lead-free (0.86− x )Bi 0.5 Na 0.5 TiO 3 -0.14Bi 0.5 K 0.5 TiO 3 - x BaZrO 3 piezoelectric ceramics were successfully fabricated using a conventional solid-state reaction method. The relative densities, crystal structures, dielectric constant, electric field-induced polarization loops, and electric field-induced strain curves of the sintered piezoelectric ceramics were analyzed. All the piezoelectric ceramics were well sintered with a single perovskite structure and a high relative density of ~ 95%. The x-ray diffraction patterns of the (0.86− x )Bi 0.5 Na 0.5 TiO 3 -0.14Bi 0.5 K 0.5 TiO 3 - x BaZrO 3 piezoelectric ceramics indicate a rhombohedral-to-tetragonal phase transition as a function of x . The BaZrO 3 addition reduces the ferroelectricity and enhances the piezoelectricity of the (0.86− x )Bi 0.5 Na 0.5 TiO 3 -0.14Bi 0.5 K 0.5 TiO 3 - x BaZrO 3 piezoelectric ceramics. The highest piezoelectric sensor coefficient d 33 is observed in the x  = 0.01 piezoelectric ceramic, whereas the highest piezoelectric actuator coefficient d 33 * is found in the x  = 0.03 piezoelectric ceramic. Especially, the x  = 0.03 piezoelectric ceramic shows a high d 33 * of 645 pm/V with a small d 33 * variation of ~ 20% in the temperature range of 25–100°C. The investigated (0.86− x )Bi 0.5 Na 0.5 TiO 3 -0.14Bi 0.5 K 0.5 TiO 3 - x BaZrO 3 piezoelectric ceramics have a great potential for the thermal stability lead-free piezoelectric actuator applications.