Non-metallic Inorganic Materials, Department of Materials and Earth Sciences, Technical University of Darmstadt, Darmstadt, 64287, Germany.
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA.
Nat Commun. 2023 Mar 18;14(1):1525. doi: 10.1038/s41467-023-37060-4.
Reversible field-induced phase transitions define antiferroelectric perovskite oxides and lay the foundation for high-energy storage density materials, required for future green technologies. However, promising new antiferroelectrics are hampered by transition´s irreversibility and low electrical resistivity. Here, we demonstrate an approach to overcome these problems by adjusting the local structure and defect chemistry, delivering NaNbO-based antiferroelectrics with well-defined double polarization loops. The attending reversible phase transition and structural changes at different length scales are probed by in situ high-energy X-ray diffraction, total scattering, transmission electron microcopy, and nuclear magnetic resonance spectroscopy. We show that the energy-storage density of the antiferroelectric compositions can be increased by an order of magnitude, while increasing the chemical disorder transforms the material to a relaxor state with a high energy efficiency of 90%. The results provide guidelines for efficient design of (anti-)ferroelectrics and open the way for the development of new material systems for a sustainable future.
可逆的场诱导相变定义了反铁电钙钛矿氧化物，并为未来绿色技术所需的高能量存储密度材料奠定了基础。然而，有前途的新型反铁电体受到相变不可逆性和低电阻率的阻碍。在这里，我们通过调整局部结构和缺陷化学来克服这些问题，提供了基于 NaNbO 的反铁电体，具有明确定义的双极化循环。通过原位高能 X 射线衍射、全散射、透射电子显微镜和核磁共振波谱研究了不同尺度上的可逆相变和结构变化。我们表明，反铁电成分的储能密度可以提高一个数量级，而增加化学无序会将材料转变为具有 90%高效率的弛豫体状态。研究结果为（反）铁电体的有效设计提供了指导，并为开发可持续未来的新材料系统开辟了道路。
