To reach the full potential of polymer dielectrics in advanced electronics and electrified transportation, it calls for efficient operation of high-energy-density dielectric polymers under high voltages over a wide temperature range. Here, the polymer composites consisting of the boron nitride nanosheet/polyetherimide and TiO₂ nanorod arrays/polyetherimide layers are reported. The layered composite exhibits a much higher dielectric constant than the current high-temperature dielectric polymers and composites, while simultaneously retaining low dielectric loss at elevated temperatures and high applied fields. Consequently, the layered polymer composite presents much improved capacitive performance than the current dielectric polymers and composites over a temperature range of 25–150 °C. Moreover, the excellent capacitive performance of the layered composite is achieved at an applied field that is about 40% lower than the typical field strength of the current polymer composites with the discharged energy densities of >3 J cm⁻³ at 150 °C. Remarkable cyclability and dielectric stability are established in the layered polymer nanocomposites. This work addresses the current challenge in the enhancement of the energy densities of high-temperature dielectric polymers and demonstrates an efficient route to dielectric polymeric materials with high energy densities and low loss over a broad temperature range.

中文翻译：

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层状聚合物纳米复合材料在宽温度范围内的超高储能性能

为了充分发挥聚合物电介质在先进电子产品和电气化运输中的潜力，需要高能量密度的电介质聚合物在高电压和宽温度范围内有效运行。这里，由氮化硼纳米片/聚醚酰亚胺和 TiO ₂组成的聚合物复合材料报道了纳米棒阵列/聚醚酰亚胺层。层状复合材料比目前的高温介电聚合物和复合材料具有更高的介电常数，同时在高温和高外加场下保持低介电损耗。因此，在 25-150 °C 的温度范围内，层状聚合物复合材料的电容性能比当前的介电聚合物和复合材料要好得多。此外，层状复合材料的优异电容性能是在外加场下实现的，该场强比当前聚合物复合材料的典型场强低约 40%，放电能量密度 >3 J cm ^-3在 150°C。在层状聚合物纳米复合材料中建立了显着的循环性和介电稳定性。这项工作解决了当前在提高高温介电聚合物能量密度方面的挑战，并展示了一种在宽温度范围内具有高能量密度和低损耗的介电聚合物材料的有效途径。