High-Performance Aqueous Supercapacitors Based on a Self-Doped n-Type Conducting Polymer

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Environmentally-benign materials are crucial for scalable energy storage.
• Conjugated polymers offer a greener alternative to traditional materials.
• A lack of n-doped conducting polymers limits high-rate performance in full cells.

Purpose of the Study:

• To demonstrate the use of a self-doped n-doped conjugated polymer, poly(benzodifurandione) (PBDF), for aqueous supercapacitors.
• To evaluate the electrochemical performance and stability of PBDF.
• To explore performance enhancements with reduced graphene oxide (rGO) and in different cell configurations.

Main Methods:

• Fabrication of aqueous supercapacitors using PBDF.
• Cyclic voltammetry and galvanostatic charge-discharge measurements to assess capacitance and stability.
• Electrochemical impedance spectroscopy to understand charge storage mechanisms.
• Testing in symmetric and asymmetric membrane-less cells.

Main Results:

• PBDF exhibited a specific capacitance of 202 ± 3 F g^-1, retaining 81% after 5000 cycles at 10 A g^-1.
• High-rate performances up to 100 A g^-1 were achieved.
• Adding rGO improved capacitance to 288 ± 8 F g^-1 and enabled rates of 270 A g^-1.
• PBDF in membrane-less cells showed 83% capacitance retention after 100,000 cycles at 10 A g^-1.

Conclusions:

• Self-doped n-doped PBDF is a promising material for high-performance, stable aqueous supercapacitors.
• PBDF offers a sustainable energy storage solution without additives or binders.
• The material demonstrates potential for scalable and environmentally friendly energy storage applications.