Abstract Composite films of KBiFe2O5 and PVA were prepared with a varied weight percentage of PVA by spin coating method on platinised silicon wafer. The composite films were characterised for dielectric and ferroelectric properties in comparison to pure KBiFe2O5thick film. The frequency dependent permittivity measurement indicated a higher contribution of space charge/interfacial polarization in KBiFe2O5 thick film than that in the KBiFe2O5 -PVA composite films. The ferroelectric properties in composite films were enhanced due to the reduction in leakage current and they showed well saturated polarization hysteresis loops. The remanent polarization value in KBiFe2O5 -PVA composite film (Pr = 3.7 μC/cm2) was found to be 2.5 times higher than that of the pure KBiFe2O5 film (Pr = 1.45 μC/cm2) and with the increase in PVA percentage, the remanent polarization values also increased. The space charge dominated conduction in pure KBiFe2O5 became transformed to field assisted ionic conduction in the KBiFe2O5 composite films. The polymeric matrix in KBiFe2O5 composites helped in reducing the leakage current of pure KBiFe2O5 by four orders of magnitude and further reduced with the increase in the PVA content in the composite. The composite films showed fatigue free polarization even after 108 switching cycles whereas the polarization degradation in KBiFe2O5 film was 30% around 108switching cycles.

中文翻译：

---

改善 KBiFe2O5-聚合物复合薄膜的铁电性能

摘要 采用旋涂法在镀铂硅片上制备了不同重量百分比的 PVA 和 KBiFe2O5 复合薄膜。与纯 KBiFe2O5 厚膜相比，复合膜具有介电和铁电特性。频率相关的介电常数测量表明，KBiFe2O5 厚膜中空间电荷/界面极化的贡献高于 KBiFe2O5 -PVA 复合膜中的空间电荷/界面极化贡献。由于漏电流的减少，复合薄膜的铁电性能得到增强，并且它们显示出饱和的极化滞后回线。发现 KBiFe2O5 -PVA 复合薄膜的剩余极化值 (Pr = 3.7 μC/cm2) 是纯 KBiFe2O5 薄膜 (Pr = 1.45 μC/cm2) 的 2.5 倍，并且随着 PVA 百分比的增加，剩余极化值也增加。纯 KBiFe2O5 中空间电荷主导的传导转变为 KBiFe2O5 复合膜中的场辅助离子传导。KBiFe2O5 复合材料中的聚合物基体有助于将纯 KBiFe2O5 的漏电流降低四个数量级，并随着复合材料中 PVA 含量的增加而进一步降低。即使在 108 次开关循环后，复合薄膜也显示出无疲劳极化，而 KBiFe2O5 薄膜的极化衰减在 108 次开关循环左右为 30%。KBiFe2O5 复合材料中的聚合物基体有助于将纯 KBiFe2O5 的漏电流降低四个数量级，并随着复合材料中 PVA 含量的增加而进一步降低。即使在 108 次开关循环后，复合薄膜也显示出无疲劳极化，而 KBiFe2O5 薄膜的极化衰减在 108 次开关循环左右为 30%。KBiFe2O5 复合材料中的聚合物基体有助于将纯 KBiFe2O5 的漏电流降低四个数量级，并随着复合材料中 PVA 含量的增加而进一步降低。即使在 108 次开关循环后，复合薄膜仍显示出无疲劳极化，而 KBiFe2O5 薄膜的极化衰减在 108 次开关循环左右为 30%。