Scalable self-assembly interfacial engineering for high-temperature dielectric energy storage

Chao Wu; Anna Marie LaChance; Mohamadreza Arab Baferani; Kuangyu Shen; Zongze Li; Zaili Hou; Ningzhen Wang; Yifei Wang; Luyi Sun; Yang Cao

doi:10.1016/j.isci.2022.104601

Scalable self-assembly interfacial engineering for high-temperature dielectric energy storage

iScience. 2022 Jun 11;25(7):104601. doi: 10.1016/j.isci.2022.104601. eCollection 2022 Jul 15.

Authors

Chao Wu¹, Anna Marie LaChance^{2

3}, Mohamadreza Arab Baferani^{1

4}, Kuangyu Shen^{2

3}, Zongze Li^{1

4}, Zaili Hou^{2

3}, Ningzhen Wang¹, Yifei Wang¹, Luyi Sun^{2

3}, Yang Cao^{1

4}

Affiliations

¹ Electrical Insulation Research Center, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
² Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
³ Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, USA.
⁴ Department of Electrical and Computer Engineering, University of Connecticut, Storrs, CT 06269, USA.

Abstract

Flexible polymer dielectrics which can function well at elevated temperatures continue to be significant in harsh condition energy storage. However, state-of-the-art high-temperature polymers traditionally designed with conjugated structures for better thermal stability have compromised bandgaps and charge injection barriers. Here, we demonstrate a self-assembled polyvinyl alcohol (PVA)/montmorillonite (MMT) coating to impede charge carriers injecting into the polyimide (PI) polymer film. The anisotropic conductivity of the 2D nanolayered coating further dissipates the energy of charges through tortuous injection pathways. With the coating, high field pre-breakdown conduction measurement and space-charge profiling of PI films reveal a clear shifting of the dominant mode of conduction from the bulk-limited hopping to Schottky-injection limited conduction. The coating thus imparts PI films with a significantly suppressed electrical conduction (∼10×), and substantially improved discharge efficiency (7×) and energy density (2.7×) at 150°C. The facile and scalable flow-induced fabrication unleash enormous applications for harsh condition electrification.

Keywords: Energy systems; Interface science; Materials science.