Grotthuss Proton-Conductive Covalent Organic Frameworks for Efficient Proton Pseudocapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Covalent organic frameworks (COFs) are crystalline porous polymers.
• Proton conduction is crucial for efficient energy storage devices.
• Developing advanced electrode materials for supercapacitors is an ongoing challenge.

Purpose of the Study:

• To synthesize novel, robust, hydrophilic COFs with intrinsic proton conduction.
• To investigate the potential of these COFs as pseudocapacitance electrode materials.
• To enhance the performance of COF-based supercapacitors through hybridization with carbon nanotubes.

Main Methods:

• Synthesis of two crystalline, hydrophilic covalent organic frameworks (COFs).
• Incorporation of redox-active azo groups for proton-coupled electron transfer.
• In situ hybridization of COFs with carbon nanotubes to form composite electrodes.

Main Results:

• The COF-carbon nanotube composite demonstrated a specific capacitance of 440 F/g at 0.5 A/g.
• The supercapacitor retained 90% capacitance after 10,000 cycles.
• The asymmetric supercapacitor achieved an energy density of 71 Wh/kg and a power density of 42 kW/kg.

Conclusions:

• This study presents the first pseudocapacitors utilizing Grotthuss proton-conductive organic materials.
• The developed COF-based supercapacitors exhibit superior energy and power densities compared to existing COF systems.
• These findings highlight the potential of COFs for next-generation energy storage applications.