Large piezoelectricity and high Curie temperature in novel bismuth ferrite‐based ferroelectric ceramics
Zhuo Yu, Jiangtao Zeng, Liaoying Zheng, Wenbing Liu, Guorong Li, A. Kassiba
Abstract
Abstract The requirement for ferroelectric ceramics with a high Curie temperature and a high piezoelectric coefficient remains an important research task for high‐temperature sensors and actuators applications. (0.76‐x)BiFeO 3‐ 0.24 PbTiO 3‐ x Ba(Sn 0.2 Ti 0.8 )O 3 (BF‐PT‐BST) piezoelectric ceramics were fabricated using the solid‐state reaction method. XRD analysis indicated that the incorporation of large ionic radius Ba 2+ at A‐site and nonferroelectric‐active Sn 4+ at B‐site generated a decrease in the tetragonality degree c/a. A wide multiphase coexistence region was formed with the content of BST ranging from 0.13 to 0.28. The enhanced piezoelectric coefficient ( d 33 ~ 200pC/N) was achieved while maintaining a high Curie temperature ( T C ~ 500°C) and a high depolarization temperature ( T d ~ 450°C) for the composition of 0.6BF‐24PT‐0.16BST. TEM patterns provided clear evidence for the presence of nanodomains (~2nm) would be the predominant source for the enhanced piezoelectricity for the composition x = 0.20. The designed BF‐PT‐BST ternary system provides great potential for high‐temperature piezoelectric applications.