Dielectric capacitors are irreplaceable energy-storage components in pulsed power systems, but the low energy density (U_e) of existing material systems restricts their miniaturization and further application. In this work, a novel polymer/ceramic nanocomposite is fabricated using core-shell BaTiO₃@SiO₂ ([email protected]) structures with a diameter less than 10 nm. Such ultrafine nanostructure not only provides a high insulating SiO₂ layer to optimize the microstructure and dielectric response as normal core-shell structures, but also has almost tenfold larger interfaces than conventional 100 nm fillers to realize a high polarization, which can effectively improve the breakdown strength as well as the electrical displacement of the composite simultaneously. With a simple and universal 0–3 type structure, in which 0-dimentional nanoparticles are embedded in a 3-dimentional connected polymer matrix, the [email protected]/PVDF nanocomposite shows outstanding energy storage performance with U_max = 11.5 J/cm³ at 420 kV/mm. Experimental result and phase field simulation both confirm the superiority of the ultrafine nanostructures in enhancing the energy density of the dielectric nanocomposite, providing a new technological way for the design of high energy-density composites.

介电电容器是脉冲功率系统中不可替代的储能组件，但是现有材料系统的低能量密度（U _e）限制了它们的小型化和进一步应用。在这项工作中，使用直径小于10 nm的核-壳BaTiO ₃ @SiO ₂（[电子邮件保护]）结构制造了一种新型的聚合物/陶瓷纳米复合材料。这种超细纳米结构不仅提供了高绝缘性的SiO ₂层可以优化微结构和介电响应，就像普通的核-壳结构一样，而且具有比传统100 nm填料大近十倍的界面，以实现高极化，可以有效地提高击穿强度和复合材料的电位移。具有简单且通用的0–3型结构，其中0维纳米粒子嵌入3维连接的聚合物基体中，[受电子邮件保护] / PVDF纳米复合材料显示出出色的能量存储性能，U _max = 11.5 J / cm ³电压为420 kV / mm。实验结果和相场模拟都证实了超细纳米结构在增强介电纳米复合材料能量密度方面的优越性，为设计高能量密度复合材料提供了新的技术途径。