Superior Capacitive Energy Storage Enabled by Molecularly Interpenetrating Interfaces in Layered Polymers

Area of Science:

• Materials Science
• Polymer Science
• Electrical Engineering

Background:

• Polymer dielectrics are crucial for electronics and power systems but have low energy density (Ue) due to low dielectric constant (K) and inverse K-breakdown strength (Eb) relationship.
• Conventional layered polymers face limitations in simultaneously improving dielectric properties and mechanical strength while preventing electrical conduction.

Purpose of the Study:

• To present a scalable approach for all-organic dielectric polymers with high energy density (Ue) and charge-discharge efficiency (η).
• To overcome the limitations of conventional layered polymers by designing molecularly interpenetrating interfaces.

Main Methods:

• Utilized designed molecularly interpenetrating interfaces in all-organic dielectric polymers.
• Investigated distinctive intermolecular interactions and microstructural changes experimentally and theoretically.
• Fabricated large-area films with high uniformity and capacitive stability.

Main Results:

• Achieved simultaneous improvements in dielectric responses (K) and mechanical strength.
• Inhibited electrical conduction, a key challenge in conventional polymers.
• Obtained high energy density (Ue) of 22.89 J cm⁻³ with charge-discharge efficiency (η) ≥ 90%.
• Demonstrated outstanding capacitive stability over 500,000 cycles.

Conclusions:

• Molecularly interpenetrating interfaces offer a novel strategy for high-performance polymer dielectrics.
• The developed materials significantly outperform current layered polymer dielectrics for electrical energy storage.
• This approach provides a practical route to scalable, high-Ue polymer dielectrics.