Li Ziwei, Qin Hongmei, Song Jinhui, Liu Man, Zhang Xiaolin, Wang Shan, Xiong Chuanxi
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Hubei Engineering Research Center for Green & Precision Material Forming, Wuhan University of Technology, Wuhan 430070, China.
Polymers (Basel). 2022 Jul 19;14(14):2918. doi: 10.3390/polym14142918.
Advanced polymer dielectrics with high energy density at elevated temperatures are highly desired to meet the requirements of modern electronic and electrical systems under harsh conditions. Herein, we report a novel polyimide/magnesium oxide (PI/MgO) nanodielectric that exhibits high energy storage density () and charge-discharge efficiency () along with excellent cycling stability at elevated temperatures. Benefiting from the large bandgap of MgO and the extended interchain spacing of PI, the composite films can simultaneously achieve high dielectric constant and high breakdown strength, leading to enhanced energy storage density. The nanocomposite film doped with 0.1 vol% MgO can achieve a maximum of 2.6 J cm and a of 89% at 450 MV m and 150 °C, which is three times that of the PI film under the same conditions. In addition, embedding ultralow content of inorganic fillers can avoid aggregation and facilitate its large-scale production. This work may provide a new paradigm for exploring polymer nanocomposites with excellent energy storage performance at high temperatures and under a high electric field.
在高温下具有高能量密度的先进聚合物电介质对于满足现代电子和电气系统在恶劣条件下的要求非常必要。在此，我们报道了一种新型聚酰亚胺/氧化镁（PI/MgO）纳米电介质，其在高温下表现出高储能密度（）和充放电效率（）以及优异的循环稳定性。受益于MgO的大带隙和PI的链间间距扩展，复合薄膜能够同时实现高介电常数和高击穿强度，从而提高储能密度。掺杂0.1体积%MgO的纳米复合薄膜在450 MV/m和150°C下可实现最大储能密度为2.6 J/cm³和充放电效率为89%，这是相同条件下PI薄膜的三倍。此外，嵌入超低含量的无机填料可以避免团聚并便于其大规模生产。这项工作可能为探索在高温和高电场下具有优异储能性能的聚合物纳米复合材料提供新的范例。
