Abstract Dielectric polymer/composites films with excellent capacitive performance has initiated enormous interest from both academic and industry because of their great potential as flexible and light-weight electrostatic capacitors for modern electric and electronic systems. In this work, we report a novel flexible dielectric composite film consisting of poly (vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) and dopamine-modified metal-organic frameworks Co3 [Co(CN)6]2 (D-M) with excellent capacitive performance for energy storage application. It is found that the D-M show good compatibility with P(VDF-HFP), permitting a high breakdown strength for composites. Meanwhile, the large specific surface area and special porous three-dimensional nanostructure of D-M also has the effect of raising dielectric performance while eliminating the inherent ferroelectric loss of P(VDF-HFP), resulting in considerably promoted discharge energy density. Furthermore, D-M is found to favor the formation of γ-phase in P(VDF-HFP), which is also advantageous to raise the discharge energy density. Upon a small loading of 0.6 wt% D-M, the composites perform a maximum discharge energy density of 11.89 J/cm3 and discharge efficiency of 71.28% at 350 MV/m, which are 3.04 times and 1.25 times those of the pure P(VDF-HFP) film, respectively. For the first time, we demonstrate that the applicability of flexible D-M/P(VDF-HFP) dielectric composites as advanced electrostatic capacitors, providing a new sight for the design of dielectrics with high capacitive performance.

中文翻译：

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通过使用多巴胺修饰的 MOF 在铁电 P(VDF-HFP) 中实现卓越的能量密度

摘要 具有优异电容性能的介电聚合物/复合薄膜因其作为现代电气和电子系统的柔性和轻型静电电容器的巨大潜力而​​引起了学术界和工业界的极大兴趣。在这项工作中，我们报告了一种由聚（偏二氟乙烯-共-六氟丙烯）（P（VDF-HFP））和多巴胺改性的金属有机骨架 Co3 [Co(CN)6]2 (DM ) 具有出色的电容性能，适用于储能应用。结果表明，DM 与 P(VDF-HFP) 具有良好的相容性，使复合材料具有较高的击穿强度。同时，DM的大比表面积和特殊的多孔三维纳米结构还具有提高介电性能的作用，同时消除了P(VDF-HFP)固有的铁电损耗，从而大大提高了放电能量密度。此外，发现DM有利于P(VDF-HFP)中γ相的形成，这也有利于提高放电能量密度。在 0.6 wt% DM 的小负载下，复合材料在 350 MV/m 下的最大放电能量密度为 11.89 J/cm3，放电效率为 71.28%，分别是纯 P(VDF- HFP) 薄膜。我们首次证明了柔性 DM/P(VDF-HFP) 介电复合材料作为高级静电电容器的适用性，