2022 journal article
Curly-Packed Structure Polymers for High-Temperature Capacitive Energy Storage
Chemistry of Materials, 34(5), 2333–2341.
Polymer film capacitors are ubiquitous in modern electronics and electric systems, but the relatively low working temperatures of polymer dielectrics limit their application in next-generation capacitors. The currently reported high-temperature polymer dielectrics rely on the construction of nanocomposites with wide band gap fillers and cross-linked networks to achieve high breakdown strength and high efficiencies. However, generating the optimal chain structure with intrinsic great high-temperature capacitive properties using a one-component polymer is still challenging. Herein, a giant discharged energy density in neat polymer has been demonstrated in a series of linear poly(arylene ether amide) (PNFA) at 150 °C, which greatly surpass all the current free-standing dielectric polymer films measured in 10 Hz. The maximum discharged energy density with efficiency above 90% of the PNFA is 2.7 J cm–3, which is about 3 times that of the state-of-the-art commercial high-temperature polymer films. The architectures of the amorphous polymers have been identified by synchrotron X-ray diffraction combined with density functional theory calculations. The origins of superior high-temperature capacitive properties are traced to the increased packing density by the curly-packed chain structure. In addition, the reported polymer could be produced using existing industrial-grade processes, which are economical and practical for large-scale applications.