XJTU research team makes new advances in flexible self-supporting antiferroelectric oxide single-crystal thin films
Antiferroelectric oxide materials have attracted widespread attention due to their significant field-induced phase transitions, large electrostrictive strain, and high polarization responses. These properties endow them with immense application potential in fields such as smart actuators, energy storage, and solid-state cooling.
With the increasing demand for next-generation flexible electronic devices, developing ultra-flexible antiferroelectric single-crystal oxide materials has become a matter of high urgency. Ultra-flexible and ultra-elastic self-supporting ferroelectric oxide single-crystal thin films have recently garnered significant interest among researchers. However, the flexibility limits and mechanisms of self-supporting single-crystal thin films for antiferroelectric oxides remain unclear.
To address this issue, Professor Liu Ming's team from the School of Electronic Science and Engineering and Professor Li Suzhi's team from the School of Materials at Xi'an Jiaotong University (XJTU) collaborated to conduct an in-depth study of the flexible mechanical behavior of antiferroelectric single-crystal thin films, making new progress.
The team selected the classic antiferroelectric material PbZrO3 as their research subject and prepared high-quality self-supporting PbZrO3 single-crystal thin films using water-soluble sacrificial layer technology. The selected area electron diffraction pattern of the thin film showed typical superlattice reflections, indicating the presence of commensurate-incommensurate modulated structures in the film.
Additionally, a method was established to apply large tensile/compressive strain to the film, further studying the effect of external bending strain on the antiferroelectric properties of the self-supporting PbZrO3 thin film, with a theoretical maximum strain of up to 3 percent. In situ scanning electron microscopy studies on the mechanical properties of the self-supporting PbZrO3 single-crystal thin film under large curvature bending showed that self-supporting PbZrO3 single-crystal thin films of different thicknesses exhibited high levels of flexibility and elasticity under bending deformation, maintaining resilience at a bending radius of about 2 micrometers. The maximum bending strain of the self-supporting PbZrO3 single-crystal thin film reached 3.5 percent, an order of magnitude greater than that of bulk materials.
This study not only reveals the intrinsic mechanism of ultra-flexibility in antiferroelectric oxides but also provides important scientific grounds for their application in the field of flexible electronics.
The findings, titled "Remarkable Flexibility in Freestanding Single-crystalline Antiferroelectric PbZrO3 Membranes", have recently been published online in the prestigious international journal Nature Communications.
Doctoral student Guo Yunting and Professor Peng Bin from the School of Electronic Science and Engineering at XJTU, along with Professor Lu Guangming from Yantai University, are the primary authors, while Professors Liu, Peng and Li are corresponding authors.