Zhao Xuan, Zhang Lei, Fan Zhenhao, Huang Yuyan, Hu Yongming, Shen Meng, Wang Zhao, He Yunbin, Wang Dawei, Zhang Qingfeng
Hubei Key Laboratory of Micro-Nanoelectronic Materials and Devices, Hubei University, Wuhan, China.
School of Materials Science&Engineering, Hubei University, Wuhan, China.
Nat Commun. 2025 Jul 1;16(1):5570. doi: 10.1038/s41467-025-60683-8.
The low dielectric constant, limited breakdown strength, and large polarization hysteresis and conduction loss constrain discharged energy density and efficiency of polymer-based dielectric capacitors at elevated temperatures. To address these challenges, the [0.8(NaBiBaSrCa)TiO-0.2NaNbO]@AlO high-entropy ferroelectric nanoparticles/polyetherimide-AlN/polyetherimide-triptycene bilayer nanocomposites are designed. The bilayer nanocomposites capitalize on advantages of high-entropy ferroelectric fillers, which contribute to the high dielectric constant and minimal hysteresis at high temperatures. Additionally, they also benefit from high thermal conductivity of AlN, enhanced rigidity and charge carrier traps in polyetherimide-triptycene, and suppressed carrier transport at the bilayer film interfaces. Consequently, the bilayer nanocomposites exhibit significantly improved dielectric constant and breakdown strength, and marked reduction in conduction loss at elevated temperatures. Remarkably, a record-high discharged energy density of 12.35 J cm is achieved in the optimized bilayer nanocomposites at 150 °C, accompanied by a large efficiency of 90.25% under an electric field of 6341 kV cm.
低介电常数、有限的击穿强度以及较大的极化滞后和传导损耗限制了聚合物基介电电容器在高温下的放电能量密度和效率。为应对这些挑战，设计了[0.8(NaBiBaSrCa)TiO-0.2NaNbO]@AlO高熵铁电纳米颗粒/聚醚酰亚胺-AlN/聚醚酰亚胺-三蝶烯双层纳米复合材料。该双层纳米复合材料利用了高熵铁电填料的优势，这些填料有助于在高温下实现高介电常数和最小滞后。此外，它们还受益于AlN的高导热性、聚醚酰亚胺-三蝶烯中增强的刚性和电荷载流子陷阱，以及双层薄膜界面处载流子传输的抑制。因此，双层纳米复合材料在高温下表现出显著提高的介电常数和击穿强度，以及传导损耗的显著降低。值得注意的是，在150°C下，优化后的双层纳米复合材料实现了创纪录的12.35 J/cm³ 的高放电能量密度，在6341 kV/cm的电场下效率高达90.25%。
