Guanhua Song,Zhibin Liu,Faqiang Zhang,Feng Liu,Yan Gu,Zhifu Liu,Yongxiang Li
A lead-free piezoelectric ceramic library of (1 − x − y)Bi0.5Na0.5TiO3–xBaTiO3–yK0.5Na0.5NbO3 [100(1 − x − y)BNT–100xBT–100yKNN] (0 ≤ x ≤ 0.12, 0 ≤ y ≤ 0.12) with 91 samples was prepared by using a high-throughput (HT) method. By comparing the performance mapping of Pr, Ec, TF–R, d33, d33* and the domain configuration to the compositions, the property diagram of the ternary library could be identified with three regions of (I) rhombohedral ferroelectric, (II) relaxor ferroelectric and (III) tetragonal ferroelectric phases. Remarkable phase-boundary effects were observed between two adjacent regions with phase coexistence features. Interestingly, the maximum d33 value was obtained near the I–III region boundary, while the maximum d33* value was obtained on the I–II region boundary. The electric field-induced rhombohedral–tetragonal phase transition at the I–III region boundary brings good piezoelectric properties. The reversible relaxor–ferroelectric phase transition near the I–II region boundary could be the origin of the enhanced depolarization effect of the samples with the recovery of the electric field, leading to high d33* values.
Lead-free BNT-BT based ceramics exhibit significant potential for achieving high piezoelectric performance. However, it is an effective strategy to achieve a morphotropic phase boundary (MPB) region with good thermal stability remains challenging. Herein, the incorporation of K 0.5 Na 0.5 NbO 3 into the Bi 0.5 Na 0.5 TiO 3 -BaTiO 3 binary system was explored, leading to a significant enhancement in both piezoelectric performance and thermal stability. The ternary BNT-BT-KNN ceramic system was systematically investigated with respect to its phase diagram, crystal structure, electrical properties, and relaxation behavior. It was observed that both the grain size and domain size gradually decrease as the KNN content increases. Remarkable electromechanical coupling factor ( k p = 0.217), exceptionally high piezoelectric properties ( d 33 = 105 pC/N), and improved ( T d = 164 °C) were achieved at BNT-BT-0.01KNN ceramics. The phase diagram of BNT-BT-KNN has been established, offering a comprehensive roadmap for the development of high-performance piezoelectric ceramics with enhanced piezoelectric responses. This work may facilitate potential applications in piezoelectric actuators.
危险品化学品经营许可证（带存储）