Lewis Acid‐Activated Charge Trapping in Dielectric Polymers for Superior High‐Temperature Electrostatic Energy Storage

Journal Article · Sun Feb 01 00:00:00 UTC 2026 · Advanced Science

DOI: https://doi.org/10.1002/advs.202517934 · OSTI ID:3009041

Fan, Lu; Xie, Zongliang; Chen, Xi; Zhang, Qingsong; Wang, Yalin; Li, He; Pang, Xi; Chen, Tiffany; Lai, Shiqi; Huang, Zhiyuan; Deatherage, Ashlin M; Gu, Hanjiang; Chen, Meng; Han, Tao; Klivansky, Liana M; Shelton, Steve W; Liu, Peng; Peng, Zongren; Xu, Ting; Zhang, Jian ; Yin, Yi; Liu, Yi

Dielectric polymer capacitors are essential for electrostatic energy storage but suffer from charge transport-induced energy losses, particularly at elevated temperatures where thermally activated charge carriers exacerbate conduction. Conventional mitigation strategies rely on introducing heterogeneous interfaces to create charge traps, complicating scalable film fabrication. A homogeneous molecular trapping mechanism would circumvent these complexities, yet remains underexplored. Herein, a charge trapping strategy is devised by modifying the lowest occupied molecular orbitals of dielectric polymers through Lewis acid-base adduct formation. The use of tris(pentafluorophenyl)boron (BCF) as a Lewis acidic molecular additive introduces deeper charge traps in commercial polyetherimide (PEI) while retaining homogeneity. With only 0.5 wt.% loading, the PEI-BCF film exhibits greatly improved breakdown strength, achieving an ultrahigh discharged energy density of 7.3 J cm-3 with excellent cycle stability at 200 °C. This work establishes a facile molecular approach to decoupling charge trapping from heterogeneous interfaces, enabling high-energy-density polymer capacitors operable under extreme thermal conditions.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: US Department of Energy; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22), Scientific User Facilities Division (SC-22.3 )
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 3009041
• Journal Information: Advanced Science, Journal Name: Advanced Science Journal Issue: 7 Vol. 13
• Country of Publication: United States
• Language: English