Recently, a team led by Fangfang Zeng from the College of Big Data and Information Engineering at Guizhou University reported a lead-free ceramic material with near-zero strain hysteresis. By meticulously designing the defect concentration and Curie temperature, the team constructed high-activity, non-freezing glassy polar nanoregins (PNRs) operating above the Curie temperature but below the Burns temperature, ultimately achieving a near-zero strain hysteresis of 1.25%. Microstructural analysis (XRD, TEM, PFM) confirmed that the long-range ferroelectric order in the material was disrupted, leading to the formation of polar nanoregions. Combined with dielectric temperature spectrum analysis, it was demonstrated that the material operates within a highly active, non-freezing region. In summary, this work successfully demonstrates the significant role of high-activity, non-freezing glassy polar nanoregions in reducing the strain hysteresis of lead-free ceramics.
On August 25, 2026, the team published their research findings in the Journal of Advanced Ceramics .
"This paper reports a strategy for achieving ultra-low strain hysteresis in lead-free ceramics by utilizing high-activity, non-freezing glassy polar nanoregions. By introducing Sb³⁺ at the B-site, acceptor doping not only generates defect dipoles that establish an internal built-in electric field, but also disrupts the long-range ferroelectric order, thereby promoting the formation of high-activity glassy polar nanoregions (HAG-PNRs). This structure significantly reduces the energy barrier for domain switching, consequently lowering the strain hysteresis of the material. Furthermore, by engineering a triple-phase coexistence (rhombohedral–tetragonal–cubic, R–T–C) structure, the energy barrier for domain reorientation is further decreased. The combination of these strategies successfully achieves near-zero strain hysteresis. Our research results provide a promising strategy for applications in high-precision actuators," said Fangfang Zeng, Associate Professor at the College of Big Data and Information Engineering, Guizhou University. Professor Zeng is an expert in the field of ceramics and has published numerous high-quality articles related to ceramics.
"Notably, the synergistic effect of multiphase coexistence and HAG-PNRs smoothens the free energy of the material, reduces the frictional damping of domain deflection, and greatly lowers the strain hysteresis. Meanwhile, the internal built-in electric field constructed through defect engineering creates an asymmetric butterfly-shaped strain curve, further reducing the strain hysteresis in the positive electric field range. By combining the effects of both strategies, we ultimately obtained nearly overlapping strain loops, achieving a near-zero strain hysteresis of 1.25%." Zeng stated: "The ultra-low strain hysteresis ceramics achieved through the synergistic action of multiple strategies provide a direction for subsequently reducing strain hysteresis in other lead-free ceramic systems."
"Through further microstructural analyses such as XRD, PFM, and TEM, the underlying physical mechanisms were elucidated, connecting macroscopic ferroelectric and strain properties with microstructure. XRD Rietveld refinement analysis and TEM SAED diffraction pattern analysis confirmed the presence of multiphase coexistence in the material. PFM amplitude and phase contrast analysis verified the existence of a large number of nanodomains, indicating that the long-range ferroelectric order had been disrupted, forming isolated polar nanoregions. Furthermore, our TEM high-resolution images also demonstrated the existence of isolated polar nanoregions, mutually corroborating the PFM observations. Finally, combined with dielectric temperature spectrum data, we confirmed that these polar nanoregions observed at the microscopic level are in a highly active, non-freezing glassy state. Through the integration of macroscopic characterization and microstructural analysis, we have explored a promising pathway for achieving ultra-low strain hysteresis in lead-free ceramics." Fangfang Zeng elaborated.
The B(1−x)ST−xSb ceramic composition exhibits a nearly linear strain loop under positive electric fields, demonstrating its potential for actuator applications. Compared with other commercial lead-free and lead-containing ceramics on the market, its outstanding performance proves its immense potential. Zeng expressed: "What we hope to convey is a strategy that can be widely applied to other lead-free ceramic systems for reducing strain hysteresis. By understanding the underlying physical principles, we anticipate that more ultra-low hysteresis ceramic materials can be developed."
Other contributors include Hongbo Li, Xudong Luo, Rongchuan He, Li Zhang, Qingquan Xiao, and Jiajun Ma from Guizhou University; Guifen Fan, Yuhan Luan, and Xiaoqiang Song from Huazhong University of Science and Technology; Dawei Wang from Harbin Institute of Technology; An Xue from Guizhou Normal University; and Xu Li from Guilin University of Technology.
About Authors
Fangfang Zeng (corresponding author), Associate Professor (Specially Appointed) at the College of Big Data and Information Engineering, Guizhou University. She has long been dedicated to the research and development of high-performance piezoelectric materials, electro-strain materials, and energy storage materials, as well as machine learning and phase-field simulation. She has published over 20 high-level papers in this field. Her research focuses on elucidating the mechanisms by which defect types, phase structure composition, and domain morphology and scale influence electrical properties, revealing the origins of high piezoelectric and electro-strain performance.
Funding:
This study received fundings from the National Key Research and Development Plan (2022YFF0706500), Construction of Science and Technology Platform of Guiyang ([2023]7-3), Industry and Education Combination Innovation Platform of Intelligent Manufacturing and Graduate Joint Training Base at Guizhou University (2020-520000-83-01-324061), Guizhou Engineering Research Center for smart services (2203-520102-04-04-298868), Guizhou Provincial Basic Research Program (Natural Science) (No. QKHJC-ZK-2023-266). National Natural Science Foundation of China (62163006, 61605153), 2025 Targeted Support Project of Guizhou Provincial Laboratory Research (Qiankehe Platform SSYS(2025) Major 003).
DOI LINK: 10.26599/JAC.2026.9221363
About Journal of Advanced Ceramics
Journal of Advanced Ceramics (JAC) is an international academic journal that presents the state-of-the-art results of theoretical and experimental studies on the processing, structure, and properties of advanced ceramics and ceramic-based composites. JAC is Fully Open Access, monthly published by Tsinghua University Press, and exclusively available via SciOpen . JAC's 2025 IF is 14, ranking in Top 1 (1/34, Q1) among all journals in "Materials Science, Ceramics" category, and its 2025 CiteScore is 24.6 (6/133) in Scopus database. ResearchGate homepage: https://www.researchgate.net/journal/Journal-of-Advanced-Ceramics-2227-8508
