Due to the development of the microelectronics industry, there is a great demand for flexible polymer dielectrics with simultaneously excellent permittivity and dielectric breakdown strength, so as to realize the prominent dielectric energy storage capability. Here, we prepare sandwich-structure films with ferroelectric dielectric Polyvinylidene Fluoride (PVDF) acting as the top layer, 2D Boron Nitride nanosheets (BNNS) as the middle layer and linear dielectric Polyimide (PI) as the bottom layer. In the films the PVDF ferroelectric layer provides high polarization, the PI linear layer enhances the dielectric breakdown strength and decreases dielectric loss, and the 2D sheet BNNS layer further strengthens the dielectric breakdown insulation. The permittivity of the multilayer films is in the range of 5.0–6.3 and dielectric loss are all below 0.03 at 100 Hz. And the sandwich-structure film with 3 mg/mL BNNS can achieve a highest dielectric energy storage of 4.35 J/cm³ at 417.6 kV/mm, surpassing that of the currently commercial BOPP by about 360 % (≈1.2 J/ cm³ under the electric field of 640 kV/mm). In addition, the multilayer films exhibit satisfactory thermal stability and mechanical properties. The multicomponent heterogeneous layered materials with simultaneously enhanced permittivity and dielectric insulating strength demonstrate a wide application prospect in the field of dielectric energy storage.

由于微电子产业的发展，对同时具有优异介电常数和介电击穿强度的柔性聚合物电介质的需求很大，以实现突出的介电储能能力。在这里，我们制备了夹层结构薄膜，其中铁电介质聚偏二氟乙烯（PVDF）作为顶层，二维氮化硼纳米片（BNNS）作为中间层，线性电介质聚酰亚胺（PI）作为底层。在薄膜中，PVDF 铁电层提供了高极化，PI 线性层提高了介电击穿强度并降低了介电损耗，二维片状 BNNS 层进一步加强了介电击穿绝缘。多层薄膜的介电常数在 5.0-6.3 范围内，介电损耗均低于 0。03 在 100 赫兹。而具有3 mg/mL BNNS的夹层结构薄膜可以实现4.35 J/cm的最高介电储能³在 417.6 kV/mm 下，超过目前商业化的 BOPP 约 360%（在 640 kV/mm 的电场下≈1.2 J/ cm ^{3 ）。}此外，多层膜表现出令人满意的热稳定性和机械性能。同时增强介电常数和介电绝缘强度的多组分异质层状材料在介电储能领域具有广阔的应用前景。