Heteroporous Donor-Acceptor Covalent Organic Framework Cathode for High-Rate-Capacity Lithium-Ion Battery

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Covalent organic frameworks (COFs) show promise for rechargeable batteries due to their defined structures.
• Designing COF cathodes with balanced ion diffusion and electron transport for high capacity remains a challenge.

Purpose of the Study:

• To engineer a novel heteroporous donor-acceptor COF (HDA-COF) with optimized electronic and ionic conductivity.
• To investigate the fast-charging capabilities and long-term stability of HDA-COF cathodes.

Main Methods:

• Utilized heteroporous donor-acceptor (D-A) engineering to create HDA-COFs.
• Combined experimental validation with theoretical calculations to verify conductivity.
• Tested HDA-COF performance in rechargeable batteries under various charge/discharge rates.

Main Results:

• HDA-COFs exhibit optimized electronic conductivity (σ_e) and ionic conductivity (σ_ions).
• Demonstrated fast-charging performance: 104 mAh g^-1 at 5 A g^-1 with a 75s charge time.
• Achieved stable cycling over 1000 cycles at 5 A g^-1 and high discharge capacity (259 mAh g^-1 at 0.05 A g^-1).

Conclusions:

• Heteroporous D-A engineering successfully optimizes both electronic and ionic conductivity in COF cathodes.
• HDA-COFs offer a promising pathway for developing high-rate-capacity rechargeable batteries.
• This approach provides insights for designing advanced COF-based energy storage materials.