Engineering hierarchical interfaces in high-temperature polymer dielectrics for electrostatic supercapacitors

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Dielectric polymers are crucial for energy storage but suffer performance loss at high temperatures due to electrical conduction.
• Existing materials struggle with reduced energy density and charge-discharge efficiency under thermal stress.

Purpose of the Study:

• To develop a universal approach for improving dielectric polymer capacitive performance across a wide temperature range.
• To engineer heterojunction interfaces in polyethersulfone (PESU) composites for enhanced energy storage.

Main Methods:

• Incorporation of one-dimensional heterojunction BaTiO3@Al2O3 nanofibers into PESU.
• Creation of hierarchical interfaces to increase charge trap density and energy levels.
• Utilizing finite element simulations to analyze breakdown path inhibition.

Main Results:

• The PESU-3 vol% BaTiO3@Al2O3 nanocomposite achieved an energy density of 7.3 J cm-3.
• Over 90% energy density retention was observed at 150 °C and 550 MV m-1.
• Heterojunction structure effectively inhibited breakdown path propagation, confirmed by simulations.

Conclusions:

• Hierarchical interface engineering with BaTiO3@Al2O3 nanofibers significantly enhances capacitive performance of PESU composites.
• This strategy effectively reduces conduction losses and improves breakdown strength at high temperatures.
• The developed nanocomposite offers a promising solution for high-temperature energy storage applications.