Lin Jimin, Qian Jin, Shi Yunjing, Wang Simin, Lin Jinfeng, Ge Guanglong, Hua Yin, Shen Bo, Zhai Jiwei
Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Functional Materials Research Laboratory, School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
ACS Appl Mater Interfaces. 2024 Dec 11;16(49):67959-67969. doi: 10.1021/acsami.4c14153. Epub 2024 Nov 22.
The impact of defects on the performance of piezoelectric materials has been a topic of considerable debate, due to the competing actions of the deteriorating effect of the defects themselves on the ceramic resistance and the positive effect on the piezoelectric performance resulting from the defect polarization. In order to probe its combined influence on piezoelectric properties, here, we designed BiFeO (BF)-based ceramics with different defect concentrations. It has been demonstrated that the incorporation of an appropriate concentration of defects into ceramics can effectively enhance their piezoelectric properties while maintaining their insulating properties. During the polarization process, both the intrinsic polarization and defect dipoles are oriented along the direction of the electric field. This occurs in the presence of a high temperature environment as well as an applied electric field, which results in a complementary enhancement of the macroscopic ferro- and piezoelectric properties. Consequently, the piezoelectric performance of BF-BT-BKT ceramics is achieved ( = 203 ± 5 pC/N, = 502 °C, = 33.05%). This work provides a framework for understanding the intrinsic structural mechanism of bismuth ferrate.
由于缺陷本身对陶瓷电阻的劣化作用与缺陷极化对压电性能的积极作用相互竞争，缺陷对压电材料性能的影响一直是一个备受争议的话题。为了探究其对压电性能的综合影响，在此，我们设计了具有不同缺陷浓度的铋铁氧体（BF）基陶瓷。结果表明，在陶瓷中引入适当浓度的缺陷可以在保持其绝缘性能的同时有效提高其压电性能。在极化过程中，本征极化和缺陷偶极子都沿电场方向取向。这在高温环境和外加电场存在的情况下发生，从而导致宏观铁电和压电性能的互补增强。因此，实现了BF-BT-BKT陶瓷的压电性能（ = 203 ± 5 pC/N， = 502 °C， = 33.05%）。这项工作为理解铋铁氧体的内在结构机制提供了一个框架。
