Rare-earth praseodymium-substituted Bi₅Ti₃FeO₁₅ exhibiting enhanced piezoelectric properties for high-temperature application

Abstract

Owing to their exceptional piezoelectric effects, piezoelectric materials play a crucial role in high-end technologies and contribute significantly to the national economy. Bismuth layer-structured ferroelectrics (BLSFs) possess high Curie temperatures, making them a focal point of research in high-temperature piezoelectric sensor devices. However, their poor piezoelectric performance and low direct-current (DC) electrical resistivity hinder their effective deployment in high-temperature applications. To overcome these shortcomings, we employed composition optimization by partially substituting bismuth ions with rare-earth praseodymium ions. This approach enhances the piezoelectric performance and improves the DC electrical resistivity by preventing the loss of volatile bismuth ions and stabilizing the bismuth oxide layer (Bi₂O₂)²⁺, thereby reducing the concentration of oxygen vacancies. Consequently, we achieved a large piezoelectric constant d₃₃ of 23.5 pC/N in praseodymium-substituted Bi₅Ti₃FeO₁₅, which is three times higher than that of pure Bi₅Ti₃FeO₁₅ (7.1 pC/N), along with a high Curie temperature T_C of 778 °C. Additionally, the optimal composition of 4 mol% praseodymium-substituted Bi₅Ti₃FeO₁₅ exhibits good thermal stability of electromechanical coupling characteristics up to 300 °C. This study holds promise for a wide array of high-temperature piezoelectric applications and has the potential to accelerate the development of high-temperature piezoelectric sensor technologies.

Keywords

Bismuth layer-structured ferroelectrics (BLSFs) / Bismuth titanate-ferrite (Bi₅Ti₃FeO₁₅) / High-temperature piezoelectric sensors / Piezoelectric ceramics

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Xin-Yu Yu: Writing - original draft, Validation, Formal analysis, Data curation. Qian Wang: Writing - review & editing, Writing - original draft, Supervision. Hui-Lin Li: Investigation, Data curation. Yi-Jun Wan: Investigation, Data curation. En-Meng Liang: Investigation, Data curation. Chun-Ming Wang: Writing - review & editing, Writing - original draft, Supervision, Resources, Project administration, Funding acquisition, Conceptualization.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 52372115), the Opening Project of Key Laboratory of Inorganic Functional Materials and Devices, Chinese Academy of Sciences (Grant No. KLIFMD202309), and Fundamental Research Funds for Central Universities. Dr. Q.W. also acknowledges financial support from the State Key Laboratory of Crystal Materials, Shandong University (Grant No. KF2308).

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