Ultrahigh discharge efficiency and energy density achieved at low electric fields in sandwich-structured polymer films containing dielectric elastomers
Ultrahigh discharge efficiency and energy density achieved at low electric fields in sandwich-structured polymer films containing dielectric elastomers
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DOI：
10.1039/c8ta11790j
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发表时间：
2019-02-28
影响因子：
11.9
通讯作者：
Wang, Hong
中科院分区：
文献类型：
--
作者：
Chen, Jie;Wang, Yifei;Wang, Hong
迫切需要介电聚合物电容器，特别是那些能够在相对低的工作电压下有效工作的介电聚合物电容器，以满足汽车和航空航天中先进电子和电力系统对小型化和可靠性日益增长的需求。然而，高性能的能量存储特性通常在高电场的应用下在介电电容器中获得。本文制备了一系列由丙烯酸橡胶介电弹性体（DE）分散在作为外层的铁电聚（偏氟乙烯-共六氟丙烯）和作为中间层的聚（甲基丙烯酸甲酯）中的全聚合物薄膜。通过优化DE含量，三明治膜的最大电位移、能量密度和放电效率得到了显著提高。值得注意的是，在300 MV m（-1）的施加场下，在具有30重量% DE的夹层膜中已经实现了11.8 J cm（-3）的高能量密度沿着以及89%的非常高的效率，这是在代表性聚合物膜中曾经实现的最好的总体性能组。在层状膜中已经证明了优异的功率密度和在弯曲循环中的能量存储性能的极大稳定性。所有这些特征提供了新的机会，设计一个新的类的分层结构的介电聚合物具有优异的能量存储能力，可以在相对较低的电场实现。
Dielectric polymer capacitors, especially those capable of operating efficiently at relatively low operating voltages, are urgently needed to meet the growing demands for miniaturization and reliability in advanced electronics and electrical power systems in automobiles and aerospace. However, high-performance energy storage properties are normally obtained in dielectric capacitors under the application of high electric fields. Herein, a series of all-polymer sandwich-structured films comprised of acrylic rubber dielectric elastomers (DE) dispersed in ferroelectric poly(vinylidene fluoride-cohexafluoropropene) as the outer layer and poly(methyl methacrylate) as the middle layer have been fabricated. The maximum electrical displacement, energy density, and discharge efficiency of the sandwiched films have been improved significantly by optimizing the DE content. Notably, a high energy density of 11.8 J cm(-3) along with a very high efficiency of 89% has been achieved in the sandwiched film with 30 wt% DE at an applied field of 300 MV m(-1), which is the best overall property set ever achieved in the representative polymer dielectrics. Excellent power density and great stability of energy storage performance over the bending cycles have been demonstrated in the layered films. All these features offer new opportunities for designing a new class of hierarchically structured dielectric polymers with excellent energy storage capability that can be achieved at relatively low electric fields.