Superior High-Temperature Capacitive Energy Storage Enabled by Interfacial Ion-Matrix Synergy in Fluoride-Composites

Area of Science:

• Materials Science
• Polymer Science
• Energy Storage

Background:

• High-temperature capacitive energy storage is vital for advanced electronics.
• Polymer dielectrics degrade at high temperatures, limiting performance.
• Conventional ceramic fillers can increase leakage conduction.

Purpose of the Study:

• To develop a new strategy for high-temperature dielectric polymers.
• To investigate the dual-functional interfacial role of fluoride nanoparticles.
• To enhance energy storage performance in polymer nanocomposites at elevated temperatures.

Main Methods:

• Fabrication of polyetherimide (PEI) nanocomposites with calcium fluoride (CaF2) nanoparticles.
• Comparative analysis with strontium fluoride (SrF2) and barium fluoride (BaF2) systems.
• Characterization of interfacial activities, breakdown strength, and insulation properties at 150°C.

Main Results:

• Fluoride nanoparticles demonstrated unique interfacial activities, neutralizing mobile ions and creating deep energy traps.
• The PEI/CaF2 nanocomposite exhibited enhanced breakdown strength and insulation at 150°C.
• An optimal PEI/2CaF2 composite achieved a discharge energy density of 6.54 J cm-3 at 150°C, outperforming other composites.

Conclusions:

• Fluoride nanoparticles play a multifunctional role in polymer dielectrics, contrary to conventional fillers.
• This interfacial design strategy offers a novel pathway for high-performance dielectric polymers under extreme conditions.
• The developed nanocomposite shows significant potential for next-generation high-temperature energy storage applications.