TiO₂ nanoarray (TNA) is usually used to improve the energy storage performance of the polymer composite; however, owing to the paradox between polarization and breakdown strength, the discharged energy density of TNA-based composite is always restricted. In this study, a novel bilayer composite with excellent energy storage performance has been designed and fabricated by combining aligned TNA and random TiO₂ nanowires (TO NWs) with poly(vinylidene fluoride) (PVDF) matrix. Interestingly, a superior discharged energy density of 16.13 J/cm³ was obtained in the (5 vol % TO NWs/TNA)–PVDF composite, which is 2.0 times higher than that of pure PVDF matrix (8.23 J/cm³) due to the simultaneously improved polarization and breakdown strength. Additionally, the corresponding energy efficiency remains high (77.37%) owing to the nonferroelectric characteristics of the TO fillers and the suppressed leakage current density. Considering the excellent and sharply incremental discharged energy density and superior energy efficiency of the (5 vol % TO NWs/TNA)–PVDF composite, this demonstrated work provides a method to obtain high discharged energy density and energy efficiency simultaneously.

中文翻译：

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优异的能量存储性能的双层复合膜结合对齐的TiO ₂纳米阵列和随机的TiO ₂纳米线与聚偏氟乙烯

TiO ₂纳米阵列（TNA）通常用于提高聚合物复合材料的储能性能。然而，由于极化强度和击穿强度之间的矛盾，TNA基复合材料的放电能量密度始终受到限制。在这项研究中，已经设计和制造了一种新型的双层复合材料，该材料通过将对准的TNA和无规TiO ₂纳米线（TO NWs）与聚偏二氟乙烯（PVDF）基质相结合而设计和制造。有趣的是，（5％TO NWs / TNA）-PVDF复合材料获得了优越的放电能量密度，为16.13 J / cm ³，是纯PVDF基质（8.23 J / cm ³）的2.0倍），因为同时提高了极化强度和击穿强度。另外，由于TO填料的非铁电特性和抑制的泄漏电流密度，相应的能量效率仍然很高（77.37％）。考虑到出色的放电能量密度和急剧增加的增量以及（5体积％TO NWs / TNA）-PVDF复合材料的出色的能源效率，这项证明的工作提供了一种同时获得高放电能量密度和能源效率的方法。