Abstract For purpose of improving the energy storage properties for the Na0.5Bi0.5TiO3 (NBT) film, NBT and BiFeO3 (BFO) were formed into solid solution. The outcomes are that the recoverable energy density (Ure) has been greatly improved, but the energy storage efficiency (η) has decreased. In this study, doping the best ratio of 0.9Na0.5Bi0.5TiO3-0.1BiFeO3 (NBT-0.1BFO) solid solution film with La3+ is to improve η by enhancing the relaxor properties, so as to improve both Ure and η for the NBT film. A sol-gel process was used to prepare lead-free NBT-0.1BFO-xLa (x = 0.000, 0.023, 0.045, 0.068, 0.090) single-phase perovskite solid solution films. La3+ replaces Bi3+ to enhance the disorder degree of cations, which disrupts the ferroelectric long-range order in the original matrix and generates nano-scale polar regions (NPRs), giving rise to enhanced relaxor properties. This further reduces the remanent polarization (Pr), thereby improving η. Consequently, the NBT-0.1BFO-0.068La film exhibits a high Ure (52.4 J/cm3) and a considerable η (60.3%) under the electric field of 2700 kV/cm, and both Ure and η are improved compared with the NBT film. Moreover, the NBT-0.1BFO-0.068La film has high temperature stability ranging from −60 °C to 80 °C, indicating that it has potential application value for energy storage capacitors.

中文翻译：

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无铅 NBT-0.1BFO-0.068La 弛豫铁电薄膜的高储能性能

摘要 为了提高Na0.5Bi0.5TiO3 (NBT)薄膜的储能性能，将NBT和BiFeO3 (BFO)固溶体。结果是可回收能量密度（Ure）大大提高，但储能效率（η）降低。本研究中，在 0.9Na0.5Bi0.5TiO3-0.1BiFeO3 (NBT-0.1BFO) 固溶体薄膜中掺杂 La3+ 的最佳比例是通过增强弛豫特性来提高 η，从而提高 NBT 的 Ure 和 η电影。采用溶胶-凝胶工艺制备无铅 NBT-0.1BFO-xLa（x = 0.000、0.023、0.045、0.068、0.090）单相钙钛矿固溶体薄膜。La3+取代Bi3+增强阳离子的无序度，破坏了原始基体中铁电长程有序，产生纳米级极区（NPRs），产生增强的弛豫特性。这进一步降低了剩余极化 (Pr)，从而提高了 η。因此，NBT-0.1BFO-0.068La薄膜在2700 kV/cm的电场下表现出高Ure（52.4 J/cm3）和相当大的η（60.3%），与NBT相比，Ure和η均有所提高电影。此外，NBT-0.1BFO-0.068La薄膜在-60°C至80°C范围内具有高温稳定性，表明其在储能电容器方面具有潜在的应用价值。