Du Houmeng, Shi Zhicheng, Hou Qing, Xia Shuimiao, Yin Peng, Dastan Davoud, Cui Hongzhi, Fan Runhua
School of Materials Science and Engineering, Ocean University of China, Qingdao 266100, China.
Institute of Photonic Chips, University of Shanghai for Science and Technology, Shanghai 200093, China.
ACS Appl Mater Interfaces. 2023 Apr 5;15(13):17103-17112. doi: 10.1021/acsami.2c21419. Epub 2023 Mar 23.
Polymers with excellent dielectric properties are strongly desired for pulsed power film capacitors. However, the adverse coupling between the dielectric constant and breakdown strength greatly limits the energy storage capability of polymers. In this work, we report an easily operated method to solve this problem via sputtering the interface of bilayer polymer films with ultralow content of gold nanoparticles. Interestingly, the gold nanoparticles can effectively block the movement of charge carriers because of the Coulomb blocking effect, yielding significantly enhanced breakdown strength. Meanwhile, the gold nanoparticles can act as electrodes to form numerous equivalent microcapacitors, resulting in an obviously enhanced dielectric constant. Impressively, the polymer film with merely 0.01 vol % gold nanoparticles exhibits an obvious dielectric constant and breakdown strength, which are 129 and 131% that of the pristine polymer film, respectively. Consequently, a high energy density which is 176% of that of the pristine polymer film is achieved, and a high efficiency of 79.2% is maintained. Moreover, this process can be well combined with the production process of commercial dielectric polymer films, which is beneficial for mass production. This work offers an easily operated way to improve the dielectric capacitive energy storage properties of polymers, which could also be applicable to other materials, such as ceramics and composites.
脉冲功率薄膜电容器强烈需要具有优异介电性能的聚合物。然而，介电常数与击穿强度之间的不利耦合极大地限制了聚合物的储能能力。在这项工作中，我们报道了一种通过溅射具有超低含量金纳米颗粒的双层聚合物薄膜界面来解决这一问题的简便操作方法。有趣的是，由于库仑阻塞效应，金纳米颗粒可以有效地阻挡电荷载流子的移动，从而显著提高击穿强度。同时，金纳米颗粒可以充当电极，形成众多等效微电容器，导致介电常数明显提高。令人印象深刻的是，仅含有0.01体积%金纳米颗粒的聚合物薄膜表现出明显的介电常数和击穿强度，分别是原始聚合物薄膜的129%和131%。因此，实现了高能量密度，为原始聚合物薄膜的176%，并保持了79.2%的高效率。此外，该工艺可以与商业介电聚合物薄膜的生产工艺很好地结合，有利于大规模生产。这项工作提供了一种简便的方法来改善聚合物的介电电容储能性能，这也可能适用于其他材料，如陶瓷和复合材料。
