π-Conjugated redox-active two-dimensional polymers as organic cathode materials.

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Redox-active two-dimensional polymers (RA-2DPs) show promise for lithium battery organic cathodes due to porosity and stability.
• Limited electrical conductivity in existing RA-2DPs hinders their practical application and device performance.

Purpose of the Study:

• To develop π-conjugated RA-2DPs with enhanced electrical conductivity.
• To improve the performance and practical relevance of organic cathode materials for lithium batteries.

Main Methods:

• A modular synthesis approach using a novel polycyclic aromatic building block (PDI-DA).
• Imine-condensation reactions followed by alkyl chain removal to form conjugated, porous networks (TAPPy-PDI and TAPB-PDI).

Main Results:

• Synthesized π-conjugated RA-2DPs (TAPPy-PDI and TAPB-PDI) with inherent porosity and high electrical conductivity.
• Demonstrated excellent rate performance and cycling stability for these materials as organic cathode materials.
• Achieved higher areal mass-loadings, enabling a practical demonstration powering LED lights.

Conclusions:

• The developed synthetic methodologies and design principles enable high-performance organic cathode materials.
• π-conjugation and permanent porosity are key factors for enhancing conductivity and ion diffusion in RA-2DPs.
• These findings pave the way for advanced organic electrode materials in energy storage devices.