Hu Yu-Qing, Mattursun Abliz, Feng Min, Liu Ning-Tao, Wang Hao-Nan, Qu Ke, Deng Xing, Guan Zhao, Yang Zhen-Zhong, Chen Bin-Bin, Zhong Ni, Duan Chun-Gang, Xiang Ping-Hua
Key Laboratory of Polar Materials and Devices (Ministry of Education), Shanghai Center of Brain-inspired Intelligent Materials and Devices, Department of Electronics, East China Normal University, Shanghai, 200241, China.
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
Small Methods. 2024 Dec;8(12):e2400258. doi: 10.1002/smtd.202400258. Epub 2024 Jul 4.
Nanoengineering polar oxide films have attracted great attention in energy storage due to their high energy density. However, most of them are deposited on thick and rigid substrates, which is not conducive to the integration of capacitors and applications in flexible electronics. Here, an alternative strategy using van der Waals epitaxial oxide dielectrics on ultra-thin flexible mica substrates is developed and increased the disorder within the system through high laser flux. The introduction of defects can efficiently weaken or destroy the long-range ferroelectric ordering, ultimately leading to the emergence of a large numbers of weak-coupling regions. Such polarization configuration ensures fast polarization response and significantly improves energy storage characteristics. A flexible BiFeO-BaTiO (BF-BT) capacitor exhibits a total energy density of 43.5 J cm and an efficiency of 66.7% and maintains good energy storage performance over a wide temperature range (20-200 °C) and under large bending deformation (bending radii ≈ 2 mm). This study provides a feasible approach to improve the energy storage characteristics of dielectric oxide films and paves the way for their practical application in high-energy density capacitors.
纳米工程化的极性氧化物薄膜因其高能量密度在能量存储领域备受关注。然而，它们大多沉积在厚且刚性的衬底上，这不利于电容器的集成以及在柔性电子器件中的应用。在此，开发了一种在超薄柔性云母衬底上使用范德华外延氧化物电介质的替代策略，并通过高激光通量增加了系统内的无序度。缺陷的引入可有效削弱或破坏长程铁电有序，最终导致大量弱耦合区域的出现。这种极化配置确保了快速的极化响应，并显著改善了能量存储特性。一种柔性BiFeO-BaTiO（BF-BT）电容器展现出43.5 J/cm³的总能量密度和66.7%的效率，并且在较宽温度范围（20-200°C）以及大弯曲变形（弯曲半径≈2毫米）下仍保持良好的能量存储性能。本研究为改善介电氧化物薄膜的能量存储特性提供了一种可行方法，并为其在高能量密度电容器中的实际应用铺平了道路。
