Liu Quanlong, Zhang Lei, Ouyang Jun, Liu Yan, Tang Zhehong, Chen Jieyu, Guo Fei, Zhou Yunpeng
College of Science, Inner Mongolia University of Technology, Hohhot 010051, China.
Discharge Plasma and Functional Materials Application Laboratory, Inner Mongolia University of Technology, Hohhot 010051, China.
Nanomaterials (Basel). 2024 Dec 13;14(24):1998. doi: 10.3390/nano14241998.
Relaxor ferroelectric film capacitors exhibit high power density with ultra-fast charge and discharge rates, making them highly advantageous for consumer electronics and advanced pulse power supplies. The Aurivillius-phase bismuth layered ferroelectric films can effectively achieve a high breakdown electric field due to their unique insulating layer ((BiO) layer)). However, designing and fabricating Aurivillius-phase bismuth layer relaxor ferroelectric films with optimal energy storage characteristics is challenging due to their inherently stable ferroelectric properties. In this work, lead-free CaBiLaTiO films were synthesized using the sol-gel technique and a weakly coupled relaxor design. On one hand, the introduction of La ions weaken the dipole-dipole interactions, thereby enhancing the relaxor behavior. Alternatively, the expansion of grain size is restricted to enhance the number of grain boundaries, which possess improved insulating properties. This leads to a higher breakdown electric field. The results indicate that CaBiLaTiO ( = 1.0) films exhibit excellent recoverable energy storage density (70 J/cm) and high energy efficiency (73%). Moreover, the film exhibited good temperature stability and frequency stability. This study not only identifies a promising material for dielectric film capacitors but also demonstrates that the energy storage capabilities of Aurivillius-phase bismuth layer ferroelectric films can be effectively modulated through a design incorporating weakly coupled relaxor characteristics.
弛豫铁电薄膜电容器具有高功率密度和超快的充放电速率，使其在消费电子产品和先进脉冲电源方面具有很大优势。由于其独特的绝缘层（（BiO）层），奥里维利乌斯相铋层状铁电薄膜能够有效地实现高击穿电场。然而，由于其固有的稳定铁电性能，设计和制造具有最佳储能特性的奥里维利乌斯相铋层弛豫铁电薄膜具有挑战性。在这项工作中，采用溶胶-凝胶技术和弱耦合弛豫设计合成了无铅CaBiLaTiO薄膜。一方面，La离子的引入削弱了偶极-偶极相互作用，从而增强了弛豫行为。另一方面，限制晶粒尺寸的扩大以增加具有改善绝缘性能的晶界数量。这导致了更高的击穿电场。结果表明，CaBiLaTiO（= 1.0）薄膜表现出优异的可恢复储能密度（70 J/cm）和高能量效率（73%）。此外，该薄膜表现出良好的温度稳定性和频率稳定性。这项研究不仅确定了一种有前途的介电薄膜电容器材料，还表明通过结合弱耦合弛豫特性的设计，可以有效地调节奥里维利乌斯相铋层铁电薄膜的储能能力。
