Molecular Bonding Engineering Enables Ultra-Stable Electrochromic Energy Storage in Flexible PEDOT Devices

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemistry

Background:

• Conducting polymers (CPs) are crucial for flexible electronics but suffer from poor stability under stress.
• Degradation mechanisms include structural damage and overoxidation, limiting device lifespan.

Purpose of the Study:

• To enhance the intrinsic stability and performance of poly(3,4-ethylenedioxythiophene) (PEDOT) for wearable electronics.
• To develop a dual-strategy molecular design for improved durability and functionality.

Main Methods:

• Employed deuterium substitution and Lewis acid-assisted polymerization to stabilize PEDOT.
• Investigated the effects of these modifications on electrochemical, optoelectronic, and mechanical properties.

Main Results:

• The deuterated PEDOT (PEDOT-D) exhibited excellent stability with <5% capacitance loss after 300,000 cycles.
• Achieved high electrochromic contrast (40.9% at 700 nm) and specific capacitance (317 F g⁻¹ at 1 A g⁻¹).
• PEDOT-D based devices showed reliable operation across a wide temperature range (-25 to 50 °C).

Conclusions:

• The dual-strategy molecular design significantly improves PEDOT durability and multifunctional performance.
• This approach provides a rational pathway for creating robust, thermally adaptive, and optically responsive flexible energy systems.