Polymer dielectric capacitors have high power density and are an integral component of electronic and power device. Currently, the limited energy density restricts their further application. In this research, a novel method was designed to optimize performance of PMMA/PVDF composite via an alternating stacked multi-layer structure. And, the five-alternating-layer of PVDF-PMMA-PVDF-PMMA-PVDF (F-A-F-A-F) composite has excellent dielectric properties, for instance, a better dielectric constant (4.52@1 kHz) and a low dielectric loss (0.034@1 kHz). The discharge energy density (Ue) of it is significantly larger than that of PMMA and PVDF. Particularly, the Ue of F-A-F-A-F composite is increased by 83.0 % (from 4.71 J/cm3 to 8.62 J/cm3) with charging-discharging efficiency of 60 % at 80 °C. Moreover, the F-A-F-A-F composite achieves an excellent stability after 40,000 cycles. This composite has a wide range of potential applications in the field of traditional dielectric capacitor due to its good energy storage performance and cycle stability.

中文翻译：

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多交替层结构 PMMA/PVDF 介电复合材料在高温下优异的储能性能


聚合物电介质电容器具有高功率密度，是电子和功率器件不可或缺的组成部分。目前，有限的能量密度限制了它们的进一步应用。在这项研究中，设计了一种通过交替堆叠多层结构优化 PMMA/PVDF 复合材料性能的新方法。并且，PVDF-PMMA-PVDF-PMMA-PVDF （F-A-F-F） 复合材料的五层交替层具有优异的介电性能，例如更好的介电常数 （4.52@1 kHz） 和低介电损耗 （0.034@1 kHz）。它的放电能量密度 （Ue） 明显大于 PMMA 和 PVDF。特别是，F-A-F-A-F 复合材料的 Ue 提高了 83.0 %（从 4.71 J/cm3 增加到 8.62 J/cm3），在 80 °C 时充放电效率为 60 %。 此外，F-A-F-A-F 复合材料在 40,000 次循环后仍能实现出色的稳定性。该复合材料由于其良好的储能性能和循环稳定性，在传统介质电容器领域具有广泛的潜在应用。